ExOne (XONE) 10-Q5 Nov 202020 Q3 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2020	Nov. 05, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Trading Symbol	XONE
Entity Registrant Name	ExOne Co
Entity Central Index Key	0001561627
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		19,187,490
Document Quarterly Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes
Entity Current Reporting Status	Yes
Entity Shell Company	false
Title of 12(b) Security	Common stock
Security Exchange Name	NASDAQ
Entity File Number	001-35806
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-1684608
Entity Address, Address Line One	127 Industry Boulevard
Entity Address, City or Town	North Huntingdon
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15642
City Area Code	724
Local Phone Number	863-9663

Condensed Statement of Consolid

Condensed Statement of Consolidated Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Revenue	$ 17,399	$ 10,884	$ 41,881	$ 35,742
Cost of sales	13,500	8,006	31,263	25,080
Gross profit	3,899	2,878	10,618	10,662
Operating expenses
Research and development	2,013	2,430	6,858	7,399
Selling, general and administrative	4,825	5,326	15,476	16,916
Gain from sale-leaseback of property and equipment			(1,462)
Total operating expenses	6,838	7,756	20,872	24,315
Loss from operations	(2,939)	(4,878)	(10,254)	(13,653)
Other expense (income)
Interest expense	54	85	171	227
Other expense (income) ̶ net	314	(134)	319	(65)
Total other (income) expense	368	(49)	490	162
Loss before income taxes	(3,307)	(4,829)	(10,744)	(13,815)
(Benefit) provision for income taxes	(34)	15	200	(686)
Net loss	$ (3,273)	$ (4,844)	$ (10,944)	$ (13,129)
Net loss per common share:
Basic	$ (0.19)	$ (0.30)	$ (0.65)	$ (0.81)
Diluted	$ (0.19)	$ (0.30)	$ (0.65)	$ (0.81)
Comprehensive loss:
Net loss	$ (3,273)	$ (4,844)	$ (10,944)	$ (13,129)
Other comprehensive income (loss):
Foreign currency translation adjustments	856	(1,387)	388	(1,580)
Comprehensive loss	$ (2,417)	$ (6,231)	$ (10,556)	$ (14,709)

Condensed Consolidated Balance

Condensed Consolidated Balance Sheet - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 39,428	$ 5,265
Restricted cash	508	978
Accounts receivable ̶ net	5,540	6,522
Current portion of net investment in sales-type leases	225	213
Inventories ̶ net	22,187	19,770
Prepaid expenses and other current assets	3,848	2,182
Total current assets	71,736	34,930
Property and equipment ̶ net	20,924	38,895
Operating lease right-of-use assets	4,278	432
Net investment in sales-type leases ̶ net of current portion	568	738
Other noncurrent assets	260	371
Total assets	97,766	75,366
Current liabilities:
Current portion of long-term debt	1,496	153
Current portion of operating lease liabilities	1,843	158
Accounts payable	4,445	5,818
Accrued expenses and other current liabilities	5,163	6,942
Current portion of contract liabilities	12,732	11,846
Total current liabilities	25,679	24,917
Long-term debt ̶ net of current portion	1,948	1,211
Operating lease liabilities ̶ net of current portion	2,435	274
Contract liabilities ̶ net of current portion	156	286
Other noncurrent liabilities	365	96
Total liabilities	30,583	26,784
Contingencies and commitments
Stockholders' equity
Common stock, $0.01 par value, 200,000,000 shares authorized, 18,988,099 (2020) and 16,346,960 (2019) shares issued and outstanding	190	163
Additional paid-in capital	205,980	176,850
Accumulated deficit	(127,892)	(116,948)
Accumulated other comprehensive loss	(11,095)	(11,483)
Total stockholders' equity	67,183	48,582
Total liabilities and stockholders' equity	$ 97,766	$ 75,366

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheet (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	18,988,099	16,346,960
Common stock, shares outstanding	18,988,099	16,346,960

Condensed Statement of Consol_2

Condensed Statement of Consolidated Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities
Net loss	$ (10,944)	$ (13,129)
Adjustments to reconcile net loss to net cash used for operations:
Depreciation	2,925	3,491
Equity-based compensation	828	1,076
Amortization of debt issuance costs	39	70
(Recoveries) provision for bad debts ̶ net	(4)	264
Provision for slow-moving, obsolete and lower of cost or net realizable value inventories ̶ net	335	37
Foreign exchange losses (gains) on intercompany transactions ̶ net	250	(127)
Gain from sale-leaseback of property and equipment	(1,462)
Gain from disposal of property and equipment ̶ net	(1)	(2)
Deferred income taxes	195
Changes in assets and liabilities, excluding effects of foreign currency translation adjustments:
Decrease in accounts receivable	1,092	2,790
Decrease in net investment in sales-type leases	158	218
Increase in inventories	(3,310)	(4,373)
Increase in prepaid expenses and other assets	(1,681)	(827)
(Decrease) increase in accounts payable	(1,679)	1,822
Increase (decrease) in accrued expenses and other liabilities	396	(1,934)
Increase in contract liabilities	248	6,301
Net cash used for operating activities	(12,615)	(4,323)
Investing activities
Capital expenditures	(772)	(613)
Proceeds from sale of property and equipment	16,229	3
Net cash provided by (used for) investing activities	15,457	(610)
Financing activities
Proceeds from borrowings on long-term debt	2,194
Proceeds from related party revolving credit facility		2,000
Payments on long-term debt	(117)	(111)
Proceeds from at-the-market offerings of common stock, net of issuance costs	27,699
Taxes related to the net share settlement of equity-based awards	(15)	(68)
Proceeds from exercise of employee stock options	858	289
Other	(63)	(10)
Net cash provided by financing activities	30,556	2,100
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	295	(187)
Net change in cash, cash equivalents, and restricted cash	33,693	(3,020)
Cash, cash equivalents, and restricted cash at beginning of period	6,243	9,140
Cash, cash equivalents, and restricted cash at end of period	39,936	6,120
Supplemental disclosure of noncash investing and financing activities
Transfer of internally developed 3D printing machines from inventories to property and equipment for internal use or leasing activities	1,434	1,635
Transfer of internally developed 3D printing machines from property and equipment to inventories for sale	2,771	485
Property and equipment included in accounts payable	113	$ 48
At-the-market offering issuance costs included in accounts payable	147
At-the-market offering issuance costs included in accrued expenses and other current liabilities	$ 66

Condensed Statement of Changes

Condensed Statement of Changes in Consolidated Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2018	$ 62,775	$ 162	$ 175,214	$ (101,853)	$ (10,748)
Beginning Balance, Shares at Dec. 31, 2018		16,234,000
Net loss	(4,496)			(4,496)
Other comprehensive income (loss)	(776)				(776)
Equity-based compensation	439		439
Exercise of employee stock options	165	$ 1	164
Exercise of employee stock options, shares		23,000
Tax withholding related to the net share settlement of equity-based awards	(68)		(68)
Common stock issued from equity incentive plan, shares		38,000
Ending Balance at Mar. 31, 2019	58,039	$ 163	175,749	(106,349)	(11,524)
Ending Balance, Shares at Mar. 31, 2019		16,295,000
Beginning Balance at Dec. 31, 2018	62,775	$ 162	175,214	(101,853)	(10,748)
Beginning Balance, Shares at Dec. 31, 2018		16,234,000
Net loss	$ (13,129)
Exercise of employee stock options, shares	40,432
Ending Balance at Sep. 30, 2019	$ 49,363	$ 163	176,510	(114,982)	(12,328)
Ending Balance, Shares at Sep. 30, 2019		16,347,000
Beginning Balance at Mar. 31, 2019	58,039	$ 163	175,749	(106,349)	(11,524)
Beginning Balance, Shares at Mar. 31, 2019		16,295,000
Net loss	(3,789)			(3,789)
Other comprehensive income (loss)	583				583
Equity-based compensation	642		642
Exercise of employee stock options	97		97
Exercise of employee stock options, shares		13,000
Common stock issued from equity incentive plan, shares		10,000
Ending Balance at Jun. 30, 2019	55,572	$ 163	176,488	(110,138)	(10,941)
Ending Balance, Shares at Jun. 30, 2019		16,318,000
Net loss	(4,844)			(4,844)
Other comprehensive income (loss)	(1,387)				(1,387)
Equity-based compensation	(5)		(5)
Exercise of employee stock options	27		27
Exercise of employee stock options, shares		4,000
Common stock issued from equity incentive plan, shares		25,000
Ending Balance at Sep. 30, 2019	49,363	$ 163	176,510	(114,982)	(12,328)
Ending Balance, Shares at Sep. 30, 2019		16,347,000
Beginning Balance at Dec. 31, 2019	$ 48,582	$ 163	176,850	(116,948)	(11,483)
Beginning Balance, Shares at Dec. 31, 2019	16,346,960	16,347,000
Net loss	$ (3,648)			(3,648)
Other comprehensive income (loss)	(838)				(838)
Equity-based compensation	292	$ 1	291
Common stock issued from equity incentive plan, shares		39,000
Ending Balance at Mar. 31, 2020	44,388	$ 164	177,141	(120,596)	(12,321)
Ending Balance, Shares at Mar. 31, 2020		16,386,000
Beginning Balance at Dec. 31, 2019	$ 48,582	$ 163	176,850	(116,948)	(11,483)
Beginning Balance, Shares at Dec. 31, 2019	16,346,960	16,347,000
Net loss	$ (10,944)
Exercise of employee stock options, shares	117,854
Ending Balance at Sep. 30, 2020	$ 67,183	$ 190	205,980	(127,892)	(11,095)
Ending Balance, Shares at Sep. 30, 2020	18,988,099	18,988,000
Beginning Balance at Mar. 31, 2020	$ 44,388	$ 164	177,141	(120,596)	(12,321)
Beginning Balance, Shares at Mar. 31, 2020		16,386,000
Net loss	(4,023)			(4,023)
Other comprehensive income (loss)	370				370
Equity-based compensation	157		157
Exercise of employee stock options	541	$ 1	540
Exercise of employee stock options, shares		73,000
Common stock issued from equity incentive plan, shares		22,000
At the market offerings of common stock, net of issuance costs	3,098	$ 4	3,094
At the market offerings of common stock,net of issuance costs, shares		383,000
Ending Balance at Jun. 30, 2020	44,531	$ 169	180,932	(124,619)	(11,951)
Ending Balance, Shares at Jun. 30, 2020		16,864,000
Net loss	(3,273)			(3,273)
Other comprehensive income (loss)	856				856
Equity-based compensation	379		379
Exercise of employee stock options	317		317
Exercise of employee stock options, shares		44,000
Tax withholding related to the net share settlement of equity-based awards	(15)		(15)
Tax withholding related to the net share settlement of equity-based awards, shares		(1,000)
Common stock issued from equity incentive plan, shares		20,000
At the market offerings of common stock, net of issuance costs	24,388	$ 21	24,367
At the market offerings of common stock,net of issuance costs, shares		2,061,000
Ending Balance at Sep. 30, 2020	$ 67,183	$ 190	$ 205,980	$ (127,892)	$ (11,095)
Ending Balance, Shares at Sep. 30, 2020	18,988,099	18,988,000

Basis of Presentation

Basis of Presentation	9 Months Ended
Basis of Presentation	Sep. 30, 2020
Accounting Policies [Abstract]
Basis of Presentation	Note 1. Basis of Presentation Organization The ExOne Company (“ExOne”) is a corporation organized under the laws of the state of Delaware. ExOne was formed on January 1, 2013, when The Ex One Company, LLC, a Delaware limited liability company, merged with and into a Delaware corporation, which survived and changed its name to The ExOne Company (the “Reorganization”). As a result of the Reorganization, The Ex One Company, LLC became ExOne, the common and preferred interest holders of The Ex One Company, LLC became holders of common stock and preferred stock, respectively, of ExOne, and the subsidiaries of The Ex One Company, LLC became the subsidiaries of ExOne. The condensed consolidated financial statements include the accounts of ExOne, its wholly-owned subsidiaries, ExOne Americas LLC (United States); ExOne GmbH (Germany); ExOne Property GmbH (Germany); and ExOne KK (Japan). Collectively, the consolidated group is referred to as the “Company”. The Company filed a shelf registration statement on Form S-3 (No. 333-223690) with the Securities and Exchange Commission on March 15, 2018. The purpose of the Form S-3 was to register various equity and debt securities. Subsidiaries of the Company are co-registrants with the Company (“Subsidiary Guarantors”), and the registration statement registered guarantees of debt securities by one or more of the Subsidiary Guarantors. The Subsidiary Guarantors are 100% owned by the Company and any guarantees by the Subsidiary Guarantors will be full and unconditional. Basis of Presentation The condensed consolidated financial statements of the Company are unaudited. The condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, considered necessary by management to fairly state the results of operations, financial position and cash flows of the Company. All material intercompany transactions and balances have been eliminated in consolidation. The results reported in these condensed consolidated financial statements are not necessarily indicative of the results that may be expected for the entire year. The December 31, 2019 condensed consolidated balance sheet data was derived from the audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). This Quarterly Report on Form 10-Q should be read in connection with the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, which includes all disclosures required by GAAP. The preparation of these condensed consolidated financial statements requires the Company to make certain judgments, estimates and assumptions regarding uncertainties that affect the reported amounts of assets, liabilities, revenue and expenses and related disclosure of contingent assets and liabilities. Areas that require significant judgments, estimates and assumptions include accounting for accounts receivable (including the allowance for doubtful accounts); inventories (including the allowance for slow-moving and obsolete inventories); product warranty reserves; contingencies; income taxes (including the valuation allowance on certain deferred tax assets and liabilities for uncertain tax positions); equity-based compensation (including the valuation of certain equity-based compensation awards issued by the Company); and testing for impairment of long-lived assets (including the identification of asset groups by management, estimates of future cash flows of identified asset groups and fair value estimates used in connection with assessing the valuation of identified asset groups). The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates. Certain amounts relating to operating lease right-of-use assets ($432), current portion of operating lease liabilities ($158) and operating lease liabilities – net of current portion ($274) in the accompanying condensed consolidated balance sheet at December 31, 2019, have been reclassified from other noncurrent assets, accrued expenses and other current liabilities and other noncurrent liabilities, respectively, to conform to current period presentation. Certain amounts in the accompanying condensed statement of consolidated cash flows have been reclassified to conform to current period presentation. COVID-19 In March 2020, the World Health Organization declared the novel strain of coronavirus a global pandemic (“COVID-19”) and recommended containment and mitigation measures worldwide. The impact of COVID-19 and the related economic, business and market disruptions are evolving rapidly, and their effects are uncertain. As a result of COVID-19, the Company was required to temporarily close its operations at its North Huntingdon, Pennsylvania facility for the period from March 23 through March 30, 2020. In response to COVID-19, the Company has incurred incremental costs associated with protecting the health and safety of the Company’s global workforce, enhanced sanitization of the Company’s global operating facilities, and information technology capabilities for employees operating remotely. Beginning in March 2020, restrictions imposed by various governmental authorities on both domestic and international shipping and travel have caused a disruption to the timing of delivery and installation of the Company’s 3D printing machines, resulting in negative impacts to the Company’s financial position, results of operations and cash flows. The duration and severity of the outbreak and its long-term impact on the Company’s business are uncertain at this time. The Company is unable to predict the impact that COVID-19 will have on its future financial position, results of operations and cash flows. Recently Issued Accounting Guidance The Company considers the applicability and impact of all Accounting Standards Updates (“ASUs”) issued by the Financial Accounting Standards Board (the “FASB”). Recently issued ASUs not listed below either were assessed and determined to be not applicable or are currently expected to have no impact on the consolidated financial statements of the Company. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments – Credit Losses.” This ASU added a new impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The CECL model applies to most debt instruments, trade receivables, lease receivables, financial guarantee contracts, and other loan commitments. The CECL model does not have a minimum threshold for recognition of impairment losses and entities will need to measure expected credit losses on assets that have a low risk of loss. As a smaller reporting company pursuant to Rule 12b-2 of the Securities Exchange Act of 1934, as amended, these changes become effective for the Company on January 1, 2023. Management is currently evaluating the potential impact of these changes on the consolidated financial statements of the Company.

Liquidity

Liquidity	9 Months Ended
Liquidity	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Liquidity	Note 2. Liquidity The Company has incurred a net loss in each of its annual periods since its inception. As shown in the accompanying condensed statement of consolidated operations and comprehensive loss, the Company incurred a net loss of $3,273 and $10,944 for the three months and nine months ended September 30, 2020, respectively. At September 30, 2020, the Company had $39,428 in unrestricted cash and cash equivalents. In addition to its unrestricted cash and cash equivalents, the Company also has access to additional capital through its $10,000 related party revolving credit facility (Note 12). Since its inception, the Company has received cumulative unrestricted net proceeds from the sale of its common stock (through its initial public offering and subsequent public offerings, including at-the-market offerings) of $195,847 to fund its operations. The Company maintains additional access to capital through its active shelf registration statement (Note 1) which allows for the sale of various equity or debt instruments up to an aggregate amount of $125,000 (including the at-the-market offerings further described below). In June 2020, the Company entered into an equity distribution agreement (the “Oppenheimer Equity Distribution Agreement”) with Oppenheimer & Company, Inc. (“Oppenheimer”) pursuant to which Oppenheimer agreed to act as sales agent in the sale of up to $25,000 in the aggregate of ExOne common stock in “at-the-market offerings” as defined in Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”). Sales of common stock under the Oppenheimer Equity Distribution Agreement ended in September 2020 when the offering limit ($25,000) was reached. Following completion of this offering, in September 2020, the Company entered into a separate equity distribution agreement (the “Canaccord Equity Distribution Agreement”) with Canaccord Genuity LLC (“Canaccord”), pursuant to which Canaccord agreed to act as sales agent in the sale of up to $25,000 in the aggregate of ExOne common stock in “at-the-market offerings” as defined in Rule 415 under the Securities Act. The terms of both the Oppenheimer Equity Distribution Agreement and the Canaccord Equity Distribution Agreement require a 3.0% commission on the sale of ExOne common stock as well as reimbursement of certain expenses incurred by the sales agent. During the three months ended September 30, 2020, the Company sold 2,060,878 shares of common stock in the above-described at-the market offerings (1,822,274 shares under the Oppenheimer Equity Distribution Agreement and 238,604 shares under the Canaccord Equity Distribution Agreement) at an average selling price of $12.26 per share, resulting in net proceeds to the Company (after deducting commissions) of $24,512. During the nine months ended September 30, 2020, the Company sold 2,443,479 shares of common stock in the above-described at-the-market offerings (2,204,875 shares under the Oppenheimer Equity Distribution Agreement and 238,604 shares under the Canaccord Equity Distribution Agreement) at an average selling price of $11.73 per share, resulting in net proceeds to the Company (after deducting commissions) of $27,800. During the three months and nine months ended September 30, 2020, the Company incurred expenses (other than commissions) associated with at-the-market offerings of $124 and $314, respectively. At September 30, 2020, $213 of the expenses (other than commissions) associated with at-the-market offerings remained unpaid, of which $147 was included in accounts payable and $66 was included in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet. There have been no sales of shares of common stock in at-the-market offerings subsequent to September 30, 2020. Future sales of securities in at-the-market offerings under the Company’s active shelf registration statement, if any, are dependent on market conditions, which may restrict the timing and extent of any future offering of securities by the Company. In addition to net proceeds from the sale of its common stock, on April 18, 2020, the Company received additional unrestricted cash proceeds of $2,194 in connection with a Paycheck Protection Program loan (Note 13). The Company has previously exhibited its ability to modify its operating structure and support its liquidity position through various restructuring and other actions, including its 2018 global cost realignment program. In response to adverse market conditions associated with COVID-19, beginning in March 2020 and through April 2020, the Company initiated various cost savings actions including a mix of employee terminations, furloughs and pay rate reductions, as well as reductions in consulting and other expenses, all in an effort to conserve cash and maintain adequate liquidity. Management believes that the Company’s existing capital resources will be sufficient to support the Company’s operating plan. If management anticipates that the Company’s actual results will differ from its operating plan, management believes it has sufficient capabilities to enact cost savings measures to preserve capital (in addition to those further d iscussed above). The Company may also seek to raise additional capital to support its growth through the incurrence of additional debt, the sale of equity or other alternatives (including asset sales) or a combination thereof.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	9 Months Ended
Accumulated Other Comprehensive Loss	Sep. 30, 2020
Equity [Abstract]
Accumulated Other Comprehensive Loss	Note 3. Accumulated Other Comprehensive Loss The following table summarizes changes in the components of accumulated other comprehensive loss for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Foreign currency translation adjustments Balance at beginning of period $ (11,951 ) $ (10,941 ) $ (11,483 ) $ (10,748 ) Other comprehensive income (loss) 856 (1,387 ) 388 (1,580 ) Balance at end of period $ (11,095 ) $ (12,328 ) $ (11,095 ) $ (12,328 ) Foreign currency translation adjustments consist of the effect of translation of functional currency financial statements (denominated in the euro and Japanese yen) to the reporting currency of the Company (United States dollar) and certain long-term intercompany transactions between subsidiaries for which settlement is not planned or anticipated in the foreseeable future. There were no tax impacts related to income tax rate changes and no amounts were reclassified to earnings for either of the periods presented.

Loss Per Share

Loss Per Share	9 Months Ended
Loss Per Share	Sep. 30, 2020
Earnings Per Share [Abstract]
Loss Per Share	Note 4. Loss Per Share The Company presents basic and diluted loss per common share amounts. Basic loss per common share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares outstanding during the applicable period. Diluted loss per common share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares and common equivalent shares outstanding during the applicable period. As the Company incurred a net loss during each of the three months and nine months ended September 30, 2020 and 2019, basic average common shares outstanding and diluted average common shares outstanding were the same because the effect of potential shares of common stock, including stock options (654,617 – 2020 and 828,059 – 2019) and unvested restricted stock issued (199,391 – 2020 and 66,513 – 2019), was anti-dilutive. The information used to compute basic and diluted net loss per common share was as follows for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Net loss $ (3,273 ) $ (4,844 ) $ (10,944 ) $ (13,129 ) Weighted average shares outstanding (basic and diluted) 17,596,076 16,332,974 16,812,806 16,296,554 Net loss per common share: Basic $ (0.19 ) $ (0.30 ) $ (0.65 ) $ (0.81 ) Diluted $ (0.19 ) $ (0.30 ) $ (0.65 ) $ (0.81 )

Revenue

Revenue	9 Months Ended
Revenue	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Revenue	Note 5. Revenue The Company derives revenue from the sale of 3D printing machines and 3D printed and other products, materials and services. Revenue is recognized when the Company satisfies its performance obligation(s) under a contract (either implicit or explicit) by transferring the promised product or service to a customer either when (or as) the customer obtains control of the product or service. A performance obligation is a promise in a contract to transfer a distinct product or service to a customer. A contract’s transaction price is allocated to each distinct performance obligation. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring products or providing services. As such, revenue is recorded net of returns, allowances, customer discounts, and incentives. Sales, value add, and other taxes collected from customers and remitted to governmental authorities are accounted for on a net (excluded from revenue) basis. Shipping and handling costs are included in cost of sales. Certain of the Company’s contracts with customers provide for multiple performance obligations. Sales of 3D printing machines may also include optional equipment, materials, replacement components and services (installation, training and other services, including maintenance services and/or an extended warranty). Certain other cont r acts have a single performance obligation, as the promise to transfer products or services is not separately identifiable from other promises in the contract and, therefore, not distinct. For contracts with multiple performance obligations, the Company allocates the contract’s transaction price to each performance obligation using the Company’s best estimate of stand-alone selling price for each distinct product or service in the contract, which is generally based on an observable price. The Company’s revenue from products is transferred to customers at a point in time. The Company’s contracts for 3D printing machines generally include substantive customer acceptance provisions. Revenue under these contracts is recognized when customer acceptance provisions have been satisfied. For all other product sales, the Company recognizes revenue at the point in time in which the customer obtains control of the product, which is generally when product title passes to the customer upon delivery. In certain cases, title does not transfer and revenue is not recognized until the customer has received the products at its physical location. The Company’s revenue from service arrangements includes deferred maintenance contracts and extended warranties that can be purchased at the customer’s option. The Company generally provides a standard one-year warranty on the Company’s 3D printing machines, which is considered an assurance type warranty, and not considered a separate performance obligation (Note 9). Revenue associated with deferred maintenance contracts is generally recognized at a point in time when the related services are performed where sufficient historical evidence indicates that the costs of performing the related services under the contract are not incurred on a straight-line basis, with such revenue recognized in proportion to the costs expected to be incurred. Revenue associated with extended warranties is generally recognized over time on a straight-line basis over the related contract period. The Company’s revenue from service arrangements includes contracts with the federal government under fixed-fee, cost reimbursable and time and materials arrangements (certain of which may have periods of performance greater than one year). Revenue under these contracts is generally recognized over time using an input measure based upon direct costs incurred and provisional rates provided under the contracts. As such, the nature of these contracts may give rise to variable consideration, primarily based upon completion of the Company’s annual incurred cost submission filing as required by the federal government. Historically, amounts associated with variable consideration have not been significant. The Company’s revenue from service arrangements includes certain research and development services. Revenue under research and development service contracts is generally recognized over time where progress is measured in a manner that reflects the transfer of control of the promised goods or services to the customer. Depending on the facts and circumstances surrounding each research and development service contract, revenue is recognized over time using either an input measure (based on the entity’s direct costs incurred in an effort to satisfy the performance obligations) or an output measure (specifically units or parts delivered, based upon certain customer acceptance and delivery requirements). The following table summarizes the Company’s revenue by product group for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 3D printing machines $ 10,488 $ 3,972 $ 21,703 $ 16,532 3D printed and other products, materials and services 6,911 6,912 20,178 19,210 $ 17,399 $ 10,884 $ 41,881 $ 35,742 Revenue from 3D printing machines includes leasing revenue whereby the Company is the lessor of 3D printing machines to its customers. Leasing revenue is accounted for under ASU 2016-02, “Leases” (Note 10). The timing of revenue recognition, billings and cash collections results in billed receivables, unbilled receivables (contract assets) and deferred revenue and customer prepayments (contract liabilities) in the accompanying condensed consolidated balance sheet. The Company considers a number of factors in its evaluation of the creditworthiness of its customers, including past due amounts, past payment history, and current 30 to 60 days recognizes For the nine months ended September 30, 2020, the Company recognized revenue of $7,233 related to contract liabilities at January 1, 2020. There As of September 30, 2020, the notwithstanding uncertainty related to the impact of COVID-19 (Note 1) including, but not limited to, international shipping and travel restrictions brought about by COVID-19 which could have an adverse effect on the timing of delivery and installation of products and/or services to customers The Company has elected to apply the practical expedient associated with incremental costs of obtaining a contract, and as such, sales commission expense is generally Accounts receivable and net investment in sales-type leases (Note 10) are reported at their net realizable value. The Company carries its investment in sales-type leases based on discounting the minimum lease payments by the interest rate implicit in the lease, less an allowance for doubtful accounts. The Company’s estimate of the allowance for doubtful accounts related to accounts receivable and net investment in sales-type leases is based on the Company’s evaluation of customer accounts with past-due outstanding balances or specific accounts for which it has information that the customer may be unable to meet its financial obligations. Based upon review of these accounts, and management’s analysis and judgment, the Company records a specific allowance for that customer’s accounts receivable or net investment in sales-type lease balance to reduce the outstanding balance to the amount expected to be collected. The allowance is re-evaluated and adjusted periodically as additional information is received that impacts the allowance amount reserved. At September 30, 2020 and December 31, 2019, the allowance for doubtful accounts was $524 and $508, respectively. During the three months ended September 30, 2020 and 2019, the Company recorded net provision for bad debts of $15 and $414, respectively. During the nine months ended September 30, 2020 and 2019, the Company recorded net (recoveries) provision for bad debts of ($4) and $264, respectively.

Cash, Cash Equivalents, and Res

Cash, Cash Equivalents, and Restricted Cash	9 Months Ended
Cash, Cash Equivalents, and Restricted Cash	Sep. 30, 2020
Cash And Cash Equivalents [Abstract]
Cash, Cash Equivalents, and Restricted Cash	Note 6. Cash, Cash Equivalents, and Restricted Cash The following provides a reconciliation of cash, cash equivalents, and restricted cash as reported in the accompanying condensed consolidated balance sheet to the same such amounts shown in the accompanying condensed statement of consolidated cash flows as of the dates indicated: September 30, December 31, 2020 2019 Cash and cash equivalents $ 39,428 $ 5,265 Restricted cash 508 978 Cash, cash equivalents, and restricted cash $ 39,936 $ 6,243 Restricted cash at both September 30, 2020 and December 31, 2019 included $508 associated with cash collateral required by a United States bank to offset certain short-term, unsecured lending commitments associated with the Company’s corporate credit card program. Restricted cash at December 31, 2019 included $470 associated with cash collateral required by a German bank for short-term financial guarantees issued by ExOne GmbH in connection with certain commercial transactions requiring security. Refer to Note 11 for further discussion related to an amendment to this cash collateral requirement effective in February 2020. Each of the balances discussed above are considered legally restricted by the Company.

Inventories

Inventories	9 Months Ended
Inventories	Sep. 30, 2020
Inventory Disclosure [Abstract]
Inventories	Note 7. Inventories Inventories consisted of the following as of the dates indicated: September 30, December 31, 2020 2019 Raw materials and components $ 10,811 $ 8,841 Work in process 3,698 4,922 Finished goods 7,678 6,007 $ 22,187 $ 19,770 Raw materials and components consist of consumable materials and component parts and subassemblies associated with 3D printing machine manufacturing and support activities. Work in process consists of 3D printing machines and other products in varying stages of completion. Finished goods consist of 3D printing machines and other products prepared for sale in accordance with customer specifications. At September 30, 2020 and December 31, 2019, the allowance for slow-moving and obsolete inventories was $2,562 and $3,443, respectively, and has been reflected as a reduction to inventories (principally raw materials and components). The following table summarizes changes in the allowance for slow-moving and obsolete inventories for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Balance at beginning of period $ 2,493 $ 4,149 $ 3,443 $ 4,143 Provision for slow-moving and obsolete inventories ̶ net 30 63 130 194 Reductions for sale, consumption or scrap of previously reserved amounts (55 ) (376 ) (1,110 ) (482 ) Foreign currency translation adjustments 94 (152 ) 99 (171 ) Balance at end of period $ 2,562 $ 3,684 $ 2,562 $ 3,684 Reductions for sale, consumption or scrap of previously reserved amounts for the nine months ended September 30, 2020 consist principally of certain raw material and component inventories associated with the Company’s former Exerial 3D printing platform, which were disposed of during the period. There was no significant benefit or charge recorded during the period in connection with the related disposals. During the nine months ended September 30, 2020, the Company recorded a charge of $205 to cost of sales in the accompanying condensed statement of consolidated operations and comprehensive loss associated with certain inventories for which cost was determined to exceed net realizable value.

Property and Equipment

Property and Equipment	9 Months Ended
Property and Equipment	Sep. 30, 2020
Long Lived Assets [Abstract]
Property and Equipment	Note 8. Property and Equipment Property and equipment consisted of the following as of the dates indicated September 30, December 31, Economic Life 2020 2019 (in years) Land $ 3,436 $ 6,980 N/A Buildings and related improvements 10,141 25,675 5 - 40 Machinery and equipment 20,658 19,531 3 - 20 Other 6,193 7,086 3 - 20 40,428 59,272 Less: Accumulated depreciation (20,092 ) (21,478 ) 20,336 37,794 Construction-in-progress 588 1,101 Property and equipment ̶ net $ 20,924 $ 38,895 For the three months ended September 30, 2020 and 2019, depreciation expense was $817 and $1,142, respectively. For the nine months ended September 30, 2020 and 2019, depreciation expense was $2,925 and $3,491, respectively. On February 18, 2020, the Company completed a sale-leaseback transaction associated with its European headquarters and operating facility in Gersthofen, Germany (Note 10). As a result of the completion of this transaction, the Company derecognized $17,282 in net property and equipment during the three months ended March 31, 2020. Sale of the facility resulted in a gain of $1,462 during the three months ended March 31, 2020. During the three months ended September 30, 2020, as a result of continued operating losses and cash flow deficiencies, the Company identified a triggering event requiring a test for the recoverability of long-lived assets held and used at the asset group level. Assessing the recoverability of long-lived assets held and used requires significant judgments and estimates by management. For purposes of testing long-lived assets for recoverability, the Company operates as three separate asset groups: United States, Europe and Japan. In assessing the recoverability of long-lived assets held and used, the Company determined the carrying amount of long-lived assets held and used to be in excess of the estimated future undiscounted net cash flows of the related assets. The Company proceeded to determine the fair value of its long-lived assets held and used, principally through use of the market approach. The Company’s use of the market approach included consideration of market transactions for comparable assets. Management concluded that the fair value of long-lived assets held and used exceeded their carrying value, and as such, no impairment loss was recorded . A significant decrease in the market price of a long-lived asset, adverse change in the use or condition of a long-lived asset, adverse change in the business climate or legal or regulatory factors impacting a long-lived asset and continued operating losses and cash flow deficiencies associated with a long-lived asset, among other indicators, could cause a future assessment to be performed which may result in an impairment of long-lived assets held and used, which could result in a material adverse effect on the financial position and results of operations of the Company.

Product Warranty Reserves

Product Warranty Reserves	9 Months Ended
Product Warranty Reserves	Sep. 30, 2020
Product Warranties Disclosures [Abstract]
Product Warranty Reserves	Note 9. Product Warranty Reserves Substantially all of the Company’s 3D printing machines are covered by a standard one-year warranty. Generally, at the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty. Expected cost is estimated using historical experience for similar products. The Company periodically assesses the adequacy of the product warranty reserves based on changes in these factors and records any necessary adjustments if actual experience indicates that adjustments are necessary. Future claims experience could be materially different from prior results because of the introduction of new, more complex products, a change in the Company’s warranty policy in response to industry trends, competition or other external forces, or manufacturing changes that could impact product quality. In the event that the Company determines that its current or future product repair and replacement costs exceed estimates, an adjustment to these reserves would be charged to cost of sales in the period such a determination is made. The following table summarizes changes in product warranty reserves, which amounts were reflected in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Balance at beginning of period $ 603 $ 1,223 $ 866 $ 1,670 Provisions for new issuances 391 182 854 711 Payments (561 ) (409 ) (1,406 ) (1,257 ) Reserve adjustments 607 (65 ) 728 (188 ) Foreign currency translation adjustments 25 (20 ) 23 (25 ) Balance at end of period $ 1,065 $ 911 $ 1,065 $ 911

Leases

Leases	9 Months Ended
Leases	Sep. 30, 2020
Leases [Abstract]
Leases	Note 10. Leases Lessee The Company leases facilities, machinery and other equipment and vehicles under operating lease arrangements (with initial terms greater than twelve months), expiring in various years through 2026. In addition, the Company leases certain equipment and vehicles under finance lease arrangements, which are not significant. For all operating lease arrangements (with the exception of short-term lease arrangements), the Company presents at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. The Company has elected, as a practical expedient, not to separate non-lease components from lease components, and instead accounts for each separate component as a single lease component for all lease arrangements, as lessee. In addition, the Company has elected, as a practical expedient, not to apply lease recognition requirements to short-term lease arrangements, generally those with a lease term of less than twelve months, for all classes of underlying assets. In determination of the lease term, the Company considers the likelihood of lease renewal options and lease termination provisions. As a result, lease payments under these short-term lease arrangements are recognized in the accompanying condensed statement of consolidated operations and comprehensive loss on a straight-line basis over the lease term. The Company uses its incremental borrowing rate in determining the present value of lease payments, as the implicit rate of the lease arrangements is generally not readily determinable. Through July 2019, c ertain of the Company’s operating lease arrangements were with related parties under common control (Note 18). Lease cost under operating lease agreements with related parties, included within short-term lease cost below, was $4 and $28 for the three and nine months ended September 30, 2019, respectively. Future minimum lease payments of operating lease arrangements (with initial terms greater than twelve months) : 2020 $ 510 2021 2,009 2022 1,973 2023 33 2024 12 Thereafter 2 Total minimum lease payments 4,539 Less: Present value discount (261 ) Total operating lease liabilities $ 4,278 For the three months and nine months ended September 30, 2020, l ease cost under operating lease arrangements was $527 and $1,560, including $24 and $96 relating to short-term lease arrangements, respectively. For the three months and nine months ended September 30, 2019, lease cost under operating lease arrangements was $94 and $305, including $44 and $156 relating to short-term lease arrangements, respectively. Supplemental information related to operating lease arrangements was as follows as of and for the nine months ended September 30, 2020: Operating lease right-of-use assets $ 4,278 Current portion of operating lease liabilities $ 1,843 Operating lease liabilities ̶ net of current portion $ 2,435 Right-of-use assets obtained in exchange for new operating lease liabilities $ 4,876 Cash paid for amounts included in the measurement of operating lease liabilities $ 1,472 Weighted average remaining lease term (in years) 2.3 Weighted average discount rate 5.1 % On December 10, 2019, ExOne Property GmbH and ExOne GmbH, the German subsidiaries of the Company (the “German Subsidiaries”), entered into a purchase agreement (the “Purchase Agreement”) with Solidas Immobilien und Grundbesitz GmbH, a private, unaffiliated German real estate investor (the “Buyer”), for the sale of the Company’s European headquarters and operating facility in Gersthofen, Germany (the “Facility”) for a purchase price of approximately $18,500 (€17,000), of which approximately $2,200 (€2,000) was received prior to December 31, 2019. Concurrent with the execution of the Purchase Agreement, ExOne GmbH and the Buyer entered into a rental contract (the “Lease”) for the leaseback of the Facility for an initial aggregate annual rent totaling approximately $1,700 (€1,500), plus applicable taxes, which is fixed during the initial three-year five-year Lessor The Company leases machinery and equipment to customers (principally 3D printing machines and related equipment) under lease arrangements classified as either operating leases or sales-type leases. The Company’s operating lease arrangements have initial terms generally ranging from one to five years, certain of which may contain extension or termination clauses, or both. Such operating lease arrangements also generally include a purchase option to acquire the related machinery and equipment at the end of the lease term for either a fixed amount as determined at inception, or a subsequently negotiated fair market value. At September 30, 2020, the Company estimated that the total fair market value significantly exceeded the related net book value of the machinery and equipment held under the Company’s operating lease arrangements. The Company’s sales-type lease arrangements generally include transfer of ownership at the end of the lease term, and as such, the Company’s net investment in sale-type lease arrangements presented in the Company’s accompanying condensed consolidated balance sheet generally does not include an amount of unguaranteed residual value. For certain of its arrangements, the Company separates and allocates (Note 5) certain non-lease components (principally maintenance services) from lease components. Sales, value add, and other taxes collected from customers and remitted to governmental authorities are accounted for on a net (excluded from lease income) basis. In determination of the lease term, the Company considers the likelihood of lease renewal options and lease termination provisions. Additionally, certain of the Company’s lease arrangements do not qualify as sale-type leases, as collectability is not reasonably assured. The Company recognized the following components under operating and sales-type lease arrangements in the accompanying condensed statement of consolidated operations and comprehensive loss for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Operating Sales- type Operating Sales- type Operating Sales- type Operating Sales- type Revenue $ 227 $ — $ 261 $ — $ 589 $ — $ 1,287 $ — Interest income (a) $ — $ 12 $ — $ 21 $ — $ 47 $ — $ 76 (a) Interest income relating to sales-type leases is recorded as a component of revenue in the accompanying condensed statement of consolidated operations and comprehensive loss for each of the periods presented. The Company’s net investment in sales-type leases consisted of the following as of the dates indicated: September 30, December 31, 2020 2019 Future minimum lease payments receivable $ 1,413 $ 1,595 Less: Allowance for doubtful accounts (443 ) (424 ) Net future minimum lease payments receivable 970 1,171 Less: Unearned interest income (177 ) (220 ) Net investment in sales-type leases $ 793 $ 951 Future minimum lease payments of non-cancellable operating and sales-type lease arrangements as of September 30, 2020 were as follows: Operating Sales-type 2020 $ 216 $ 226 2021 273 385 2022 — 385 2023 — 417 2024 — — Thereafter — — Total minimum lease payments $ 489 $ 1,413 Less: Allowance for doubtful accounts (443 ) Less: Present value discount (177 ) Future minimum lease payments receivable $ 793

Contingencies and Commitments

Contingencies and Commitments	9 Months Ended
Contingencies and Commitments	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Contingencies and Commitments	Note 11. Contingencies and Commitments Contingencies On March 1, 2018, the Company’s ExOne GmbH subsidiary notified Voxeljet AG that it had materially breached a 2003 Patent and Know-How Transfer Agreement and asserted its rights to set-off damages as a result of the breaches against the annual license fee due from the Company under the agreement. At this time, the Company cannot reasonably estimate a contingency, if any, related to this matter. The Company is subject to various litigation, claims, and proceedings which have been or may be instituted or asserted from time to time in the ordinary course of business. Management does not believe that the outcome of any pending or threatened matters will have a material adverse effect, individually or in the aggregate, on the financial position, results of operations or cash flows of the Company. Commitments In the normal course of its operations, ExOne GmbH issues short-term financial guarantees and letters of credit to third parties in connection with certain commercial transactions requiring security through a credit facility with a German bank. On February 24, 2020, ExOne GmbH entered into an amendment and replacement of its credit facility with the German bank. The credit facility amendments included the elimination of the overdraft credit and short-term loan features of the prior agreement and replaced them with an increased capacity amount of approximately $4,100 (€3,500) for the issuance of financial guarantees and letters of credit for commercial transactions requiring security. The cash collateral requirement for the issuance of financial guarantees and letters of credit for commercial transactions requiring security was eliminated for amounts up to approximately $1,200 (€1,000) as the amendment provided the German bank with a collateral interest in the accounts receivable of ExOne GmbH. Amounts in excess of approximately $1,200 (€1,000) continue to require cash collateral under the amended credit facility. At September 30, 2020, total outstanding financial guarantees and letters of credit issued by ExOne GmbH under the amended credit facility were $583 (€497), with expiration dates ranging from October 2020 February 2023

Long-Term Debt

Long-Term Debt	9 Months Ended
Long-Term Debt	Sep. 30, 2020
Debt Disclosure [Abstract]
Long-Term Debt	Note 13. Long-Term Debt Long-term debt consisted of the following as of the dates indicated: September 30, 2020 December 31, 2019 Principal Unamortized Debt Issuance Costs Net Principal Unamortized Debt Issuance Costs Net Paycheck Protection Program loan $ 2,194 $ — $ 2,194 $ — $ — $ — Building note payable 1,266 (16 ) 1,250 1,384 (20 ) 1,364 Less: Amount due within one year (1,500 ) 4 (1,496 ) (157 ) 4 (153 ) $ 1,960 $ (12 ) $ 1,948 $ 1,227 $ (16 ) $ 1,211 On April 18, 2020, the Company entered into an unsecured promissory note (the “Note”) with an unrelated United States bank (the “Lender”) reflecting a loan in the principal amount of $2,194 (the “Loan”). The Loan was granted pursuant to the Paycheck Protection Program (the “PPP”) administered by the United States Small Business Administration (the “SBA”) as part of the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”). Pursuant to the terms of the Note, the Loan bears interest at a rate of 1.00% per annum and matures on April 18, 2022 (the “Maturity Date”). Principal and interest payments on the Loan are deferred until November 18, 2020, at which time equal installments of principal and interest will be due and payable monthly through the Maturity Date. The Note may be prepaid by the Company at any time prior to maturity without penalty. If the Company defaults on the Note, the Lender may, at its option, accelerate the maturity of the Company’s obligations under the Note. Pursuant to the terms of the PPP, the Loan, or a portion thereof, may be forgiven if Loan proceeds are used for qualifying expenses as described in the CARES Act, such as payroll costs, costs used to continue group health care benefits, mortgage interest payments, rent and utilities. The Company intends to use all or a significant majority of the Loan proceeds for qualifying expenses. The terms of the Loan, including eligibility and forgiveness, may be subject to further requirements in regulations and guidance adopted by the SBA, including the Paycheck Protection Flexibility Act enacted in June 2020. The Company has elected to account for the Loan in accordance with the terms of the Note while its forgiveness eligibility remains subject to review. On May 21, 2012, the Company entered into a building note payable with an unrelated United States bank. Terms of the building note payable include monthly payments of $18, including interest at 4.00% through May 2017, and subsequently, monthly payments of $19 including interest at the monthly average yield on United States Treasury Securities plus 3.25% for the remainder of the term through May 2027. The building note payable is collateralized by the Company’s facility located in North Huntingdon, Pennsylvania which had a carrying value of $4,838 at September 30, 2020. At December 31, 2019, the Company identified that it was not in compliance with the annual cash flow-to-debt service ratio covenant associated with the building note payable. The Company requested and was granted a waiver related to compliance with this annual covenant at December 31, 2019 and through December 31, 2020. Related to the 2019 non-compliance, there were no cross-default provisions or related impacts on other lending or financing agreements (Note 12). Future maturities of long-term debt at September 30, 2020, were as follows: 2020 $ 282 2021 1,627 2022 668 2023 188 2024 195 Thereafter 500 $ 3,460

Income Taxes

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 14. Income Taxes The (benefit) provision for income taxes for the three months ended September 30, 2020 and 2019 was ($34) and $15, respectively. The provision (benefit) for income taxes for the nine months ended September 30, 2020 and 2019 was $200 and ($686), respectively. The Company has completed a discrete period computation of its (benefit) provision for income taxes for each of the periods presented. The discrete period computation was required as a result of jurisdictions with losses before income taxes for which no tax benefit can be recognized and an inability to generate reliable estimates for results in certain jurisdictions as a result of inconsistencies in generating net operating profits (losses) in those jurisdictions. The effective tax rate for the three months ended September 30, 2020 and 2019 was 1.0% (benefit on a loss) and 0.3% (provision on a loss), respectively. The effective tax rate for the nine months ended September 30, 2020 and 2019 was 1.9% (provision on a loss) and 5.0% (benefit on a loss), respectively. For the three and nine months ended September 30, 2020 and the three months ended September 30, 2019, the effective tax rate differed from the United States federal statutory rate of 21.0% primarily due to net changes in valuation allowances for the period. For the nine months ended September 30, 2019, the effective tax rate differed from the United States federal statutory rate of 21.0% primarily due to the reversal of previously recorded liabilities for uncertain tax positions (further discussed below) and net changes in valuation allowances for the period. The Company has provided a valuation allowance for certain of its net deferred tax assets as a result of the Company not generating consistent net operating profits in certain jurisdictions in which it operates. As such, certain benefits from deferred taxes in the periods presented have been fully offset by changes in the valuation allowance for the related net deferred tax assets. The Company continues to assess its future taxable income by jurisdiction based on recent historical operating results, the expected timing of reversal of temporary differences, various tax planning strategies that the Company may be able to enact in future periods, the impact of potential operating changes on the business and forecast results from operations in future periods based on available information at the end of each reporting period. To the extent that the Company is able to reach the conclusion that net deferred tax assets are realizable based on any combination of the above factors in a single, or in multiple, taxing jurisdictions, a reversal of the related portion of the Company’s existing valuation allowances may occur. A reconciliation of the beginning and ending amount of unrecognized tax benefits (including accrued interest and penalties) was as follows for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Balance at beginning of period $ — $ 105 $ — $ 1,186 Additions based on tax positions related to the current year — — — — Additions for tax positions of prior years — 2 — 4 Reductions for tax positions of prior years — — — (1,075 ) Settlements — — — — Foreign currency translation adjustments — (5 ) — (13 ) Balance at end of period $ — $ 102 $ — $ 102 The Company includes interest and penalties related to income taxes as a component of the (benefit) provision for income taxes in the accompanying condensed statement of consolidated operations and comprehensive loss. There were no such interest or penalties included in the (benefit) provision for income taxes for any of the periods presented. At December 31, 2018, the Company’s ExOne GmbH (2010-2013) and ExOne Property GmbH (2013) subsidiaries were under examination by local taxing authorities in Germany. In January 2019, this examination was concluded without significant adjustment to previously established tax positions. As a result, during the three months ended March 31, 2019, the Company recorded a reversal of certain of its previously recorded liabilities for uncertain tax positions of $1,075, of which $257 was offset against net operating loss carryforwards.

Equity-Based Compensation

Equity-Based Compensation	9 Months Ended
Equity-Based Compensation	Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-Based Compensation	Note 15. Equity-Based Compensation On January 24, 2013, the Board adopted the 2013 Equity Incentive Plan (the “Plan”). In connection with the adoption of the Plan, 500,000 shares of common stock were reserved for issuance pursuant to the Plan, with automatic increases in such reserve available each year annually on January 1 from 2014 through 2023 equal to the lesser of 3.0% of the total outstanding shares of common stock as of December 31 of the immediately preceding year, or a number of shares of common stock determined by the Board, provided that the maximum number of shares authorized under the Plan could not exceed 1,992,241 shares, subject to certain adjustments. The maximum number of shares authorized under the Plan was reached on January 1, 2017. At September 30, 2020, 495,804 shares remained available for future issuance under the Plan Stock options and restricted stock issued by the Company under the Plan are generally subject to service conditions resulting in annual vesting on the anniversary of the date of grant over a period typically ranging between one and three years. Certain stock options and restricted stock issued by the Company under the Plan vest immediately upon issuance. Stock options issued by the Company under the Plan have contractual lives which expire over a period typically ranging between five and ten years from the date of grant, subject to continued service to the Company by the participant . On February 6, 2019, the Compensation Committee of the Board adopted the 2019 Annual Incentive Program (the “2019 Program”) as a subplan under the Plan. The 2019 Program provided an opportunity for performance-based compensation to senior executive officers of the Company, among others. The target annual incentive for each 2019 Program participant was expressed as a percentage of base salary and was conditioned on the achievement of certain financial goals (as approved by the Compensation Committee of the Board). The Compensation Committee of the Board retained negative discretion over amounts payable under the 2019 Program. During the three months ended September 30, 2019, the Company recorded a net reversal of $376 to equity-based compensation expense based on a change in the estimated outcome of the defined financial goals for 2019 under the 2019 program. On February 5, 2020, the Compensation Committee of the Board adopted the 2020 Annual Incentive Program (the “2020 Program”) as a subplan under the Plan. The 2020 Program provided an opportunity for performance-based compensation to senior executive officers of the Company, among others. The target annual incentive for each 2020 Program participant was expressed as a percentage of base salary and was conditioned on the achievement of certain financial goals (as approved by the Compensation Committee of the Board). The Compensation Committee of the Board retained negative discretion over amounts payable under the 2020 Program. During the three and nine months ended September 30, 2020, the Company recorded no equity-based compensation expense based on the estimated outcome of the defined financial goals for 2020 under the 2020 Program. The following table summarizes the total equity-based compensation expense recognized by the Company for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Equity-based compensation expense recognized: Stock options $ 127 $ 195 $ 316 $ 511 Restricted stock 244 171 490 545 Other (a) 8 (371 ) 22 20 Total equity-based compensation expense before income taxes 379 (5 ) 828 1,076 Benefit for income taxes (b) — — — — Total equity-based compensation expense net of income taxes $ 379 $ (5 ) $ 828 $ 1,076 (a) For each of the 2020 periods, Other represents expense associated with certain employee contractual amounts to be settled in equity. For each of the 2019 periods, Other represents activity associated with the 2019 Program and certain employee contractual amounts to be settled in equity. (b) The Benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 based on recorded valuation allowances against net deferred tax assets. At September 30, 2020, total future compensation expense related to unvested awards yet to be recognized by the Company was $387 for stock options and $1,664 for restricted stock. Total future compensation expense related to unvested awards yet to be recognized by the Company is expected to be recognized over a weighted-average remaining vesting period of 2.3 years. The fair value of stock options was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions for the periods indicated: Nine Months Ended September 30, 2020 2019 Weighted average fair value per stock option $5.11 - $6.20 $2.77 - $3.68 Volatility 58.0% - 58.6% 54.0% - 60.1% Average risk-free interest rate 0.2% 1.5% - 2.5% Dividend yield 0.0% 0.0% Expected term (years) 3.5 2.5 - 3.5 For certain stock option awards, volatility is estimated based on the historical volatility of the Company when the expected term of the award is less than the period for which the Company has been publicly traded. For certain stock option awards, volatility is estimated based on the historical volatilities of certain peer group companies when the expected term of the award exceeds the period for which the Company has been publicly traded. The average risk-free rate is based on a weighted average yield curve of risk-free interest rates consistent with the expected term of the awards. Expected dividend yield is based on historical dividend data as well as future expectations. Expected term is calculated using the simplified method as the Company does not have sufficient historical exercise experience upon which to base an estimate. The activity for stock options was as follows for the periods indicated: Nine Months Ended September 30, 2020 2019 Number Options Weighted Exercise Price Weighted Average Grant Date Fair Value Number Options Weighted Exercise Price Weighted Average Grant Date Fair Value Outstanding at beginning of period 854,259 $ 9.34 $ 4.49 621,986 $ 10.66 $ 5.52 Stock options granted 25,022 $ 14.40 $ 5.99 290,610 $ 7.35 $ 2.95 Stock options exercised (117,854 ) $ 7.28 $ 3.12 (40,432 ) $ 7.17 $ 3.03 Stock options forfeited (79,936 ) $ 7.85 $ 3.41 (9,773 ) $ 7.67 $ 3.70 Stock options expired (26,874 ) $ 12.02 $ 6.78 (34,332 ) $ 16.87 $ 10.30 Outstanding at end of period 654,617 $ 9.81 $ 4.75 828,059 $ 9.44 $ 4.56 Exercisable at end of period 506,295 $ 10.46 $ 5.27 403,479 $ 11.30 $ 6.02 Expected to vest at end of period 148,322 $ 7.62 $ 3.01 424,580 $ 7.68 $ 3.18 At September 30, 2020, intrinsic value associated with stock options exercisable and expected to vest was $1,479 and $705, respectively. The weighted average remaining contractual term of stock options exercisable and expected to vest at September 30, 2020, was 3.3 years and 4.0 years, respectively. Stock options with an aggregate intrinsic value of $1,096 were exercised by employees during the nine months ended September 30, 2020, resulting in proceeds to the Company from the exercise of stock options of $858. Stock options with an aggregate intrinsic value of $358 were exercised by employees during the nine months ended September 30, 2019, resulting in proceeds to the Company from the exercise of stock options of $289. The activity for restricted stock was as follows for the periods indicated: Nine Months Ended September 30, 2020 2019 Shares of Restricted Stock Weighted Average Grant Date Fair Value Shares of Restricted Stock Weighted Average Grant Date Fair Value Outstanding at beginning of period 66,513 $ 8.76 67,001 $ 8.30 Restricted stock granted 209,891 $ 9.58 66,763 $ 8.98 Restricted stock vested (77,013 ) $ 8.94 (62,251 ) $ 8.65 Restricted stock forfeited — $ — (5,000 ) $ 6.75 Outstanding at end of period 199,391 $ 9.55 66,513 $ 8.76 Restricted stock expected to vest at end of period 199,391 $ 9.55 66,513 $ 8.76 Restricted stock that vested during the nine months ended September 30, 2020 and 2019, had a fair value of $635 and $535, respectively. Participants have the option to elect net settlement for restricted stock awards. Under net settlement, the Company withholds shares of stock that would otherwise be delivered to the employee and remits cash equal to the fair value of shares withheld to the taxing authority to satisfy tax withholding obligations. During the nine months ended September 30, 2020 and 2019, the Company withheld shares with a fair value of $15 and $68, respectively, related to the net settlement of restricted stock awards.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
Fair Value Measurements	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 16. Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities, which are required to be recorded at fair value, the Company considers the principal or most advantageous market in which the Company would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as inherent risk, transfer restrictions and credit risk. The Company applies the following fair value hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: Level 1 Observable inputs such as quoted prices in active markets for identical investments that the Company has the ability to access. Level 2 Inputs include: Quoted prices for similar assets or liabilities in active markets; Quoted prices for identical or similar assets or liabilities in inactive markets; Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and Inputs that are derived principally from, or corroborated by, observable market data by correlation or other means. Level 3 Inputs that are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The Company is required to disclose its estimate of the fair value of material financial instruments, including those recorded as assets or liabilities in its consolidated financial statements, in accordance with GAAP. At September 30, 2020 and December 31, 2019, the Company had no financial instruments (assets or liabilities) measured at fair value on a recurring basis. The carrying values and fair values of other financial instruments (assets and liabilities) not required to be recorded at fair value were as follows as of the dates indicated: September 30, December 31, 2020 2019 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 39,428 $ 39,428 $ 5,265 $ 5,265 Restricted cash $ 508 $ 508 $ 978 $ 978 Debt issuance costs (a) $ 120 $ — $ 107 $ — Current portion of long-term debt (b) $ 1,496 $ 1,365 $ 153 $ 157 Long-term debt ̶ (b) $ 1,948 $ 1,954 $ 1,211 $ 1,227 (a) Represents debt issuance costs associated with the Company’s related party revolving credit facility (Note 12) of which $35 and (b) Carrying values at September 30, 2020 and December 31, 2019 are net of unamortized debt issuance costs of $16 and $20, respectively The carrying amounts of cash and cash equivalents and restricted cash approximate fair value due to their short-term maturities. The fair value of current portion of long term debt and long-term debt – net of current portion has been estimated by management based on the consideration of applicable interest rates, including certain instruments at variable or floating rates and the nominal fixed interest rate (1.0%) associated with the Company’s PPP Loan (Note 13) and other available information (including quoted prices of similar instruments available to the Company). Cash and cash equivalents and restricted cash were classified as Level 1; Current portion of long-term debt and long-term debt – net of current portion were classified as Level 2 .

Concentration of Credit Risk

Concentration of Credit Risk	9 Months Ended
Concentration of Credit Risk	Sep. 30, 2020
Risks And Uncertainties [Abstract]
Concentration of Credit Risk	Note 17. Concentration of Credit Risk During the three months and nine months ended September 30, 2020 and 2019, the Company conducted a significant portion of its business with a limited number of customers, though not necessarily the same customers for each respective period. For the three months ended September 30, 2020 and 2019, the Company’s five most significant customers represented 39.5% and 30.2% of total revenue, respectively. For the nine months ended September 30, 2020 and 2019, the Company’s five most significant customers represented 20.0% and 23.8% of total revenue, respectively. At September 30, 2020 and December 31, 2019, accounts receivable from the Company’s five most significant customers were $1,291 and $3,230, respectively.

Related Party Transactions

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Note 18. Related Party Transactions Purchases of products and/or services from related parties during the three months and nine months ended September 30, 2019 were $5 and $63, respectively. Purchases of products and/or services by the Company during the three and nine months ended September 30, 2019 primarily included website design services and leased office space (through July 2019) from related parties under common control by S. Kent Rockwell, (currently Chairman of the Board of the Company and previously the Executive Chairman and Chief Executive Officer of the Company) and the purchase of a 3D printing machine and certain ancillary equipment for $30 from an educational institution determined to be a related party on the basis that S. Kent Rockwell serves as a trustee of the educational institution. None of the transactions met a threshold requiring review and approval by the Audit Committee of the Board. There were no purchases of products and/or services from related parties during the three or nine months ended September 30, 2020. There were no amounts due to related parties associated with the purchase of products and/or services at either September 30, 2020 or December 31, 2019. The Company also receives the benefit of the corporate use of an airplane from a related party under common control by S. Kent Rockwell for no consideration. There were no such benefits received during the three months ended September 30, 2019. The Company estimates the fair market value of the benefits received during the nine months ended September 30, 2019 was $3. There were no such benefits received during the three months and nine months ended September 30, 2020. Refer to Note 12 for further discussion relating to the Company’s revolving credit facility with a related party.

Other Expense (Income) - Net

Other Expense (Income) - Net	9 Months Ended
Other Expense (Income) - Net	Sep. 30, 2020
Other Income And Expenses [Abstract]
Other Expense (Income) - Net	Note 19. Other Expense (Income) – Net Other expense (income) – net consisted of the following for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Interest income $ (4 ) $ (2 ) $ (19 ) $ (10 ) Foreign currency losses (gains) - net 299 (136 ) 262 (85 ) Other – net 19 4 76 30 $ 314 $ (134 ) $ 319 $ (65 )

Subsequent Events

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent Events	Note 20. Subsequent Events The Company has evaluated all of its activities and concluded that no other subsequent events have occurred that would require recognition in the condensed consolidated financial statements or disclosure in the notes to the condensed consolidated financial statements .

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
Basis of Presentation (Policies)	Sep. 30, 2020
Accounting Policies [Abstract]
Organization	Organization The ExOne Company (“ExOne”) is a corporation organized under the laws of the state of Delaware. ExOne was formed on January 1, 2013, when The Ex One Company, LLC, a Delaware limited liability company, merged with and into a Delaware corporation, which survived and changed its name to The ExOne Company (the “Reorganization”). As a result of the Reorganization, The Ex One Company, LLC became ExOne, the common and preferred interest holders of The Ex One Company, LLC became holders of common stock and preferred stock, respectively, of ExOne, and the subsidiaries of The Ex One Company, LLC became the subsidiaries of ExOne. The condensed consolidated financial statements include the accounts of ExOne, its wholly-owned subsidiaries, ExOne Americas LLC (United States); ExOne GmbH (Germany); ExOne Property GmbH (Germany); and ExOne KK (Japan). Collectively, the consolidated group is referred to as the “Company”. The Company filed a shelf registration statement on Form S-3 (No. 333-223690) with the Securities and Exchange Commission on March 15, 2018. The purpose of the Form S-3 was to register various equity and debt securities. Subsidiaries of the Company are co-registrants with the Company (“Subsidiary Guarantors”), and the registration statement registered guarantees of debt securities by one or more of the Subsidiary Guarantors. The Subsidiary Guarantors are 100% owned by the Company and any guarantees by the Subsidiary Guarantors will be full and unconditional. Basis of Presentation The condensed consolidated financial statements of the Company are unaudited. The condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, considered necessary by management to fairly state the results of operations, financial position and cash flows of the Company. All material intercompany transactions and balances have been eliminated in consolidation. The results reported in these condensed consolidated financial statements are not necessarily indicative of the results that may be expected for the entire year. The December 31, 2019 condensed consolidated balance sheet data was derived from the audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). This Quarterly Report on Form 10-Q should be read in connection with the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, which includes all disclosures required by GAAP. The preparation of these condensed consolidated financial statements requires the Company to make certain judgments, estimates and assumptions regarding uncertainties that affect the reported amounts of assets, liabilities, revenue and expenses and related disclosure of contingent assets and liabilities. Areas that require significant judgments, estimates and assumptions include accounting for accounts receivable (including the allowance for doubtful accounts); inventories (including the allowance for slow-moving and obsolete inventories); product warranty reserves; contingencies; income taxes (including the valuation allowance on certain deferred tax assets and liabilities for uncertain tax positions); equity-based compensation (including the valuation of certain equity-based compensation awards issued by the Company); and testing for impairment of long-lived assets (including the identification of asset groups by management, estimates of future cash flows of identified asset groups and fair value estimates used in connection with assessing the valuation of identified asset groups). The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates. Certain amounts relating to operating lease right-of-use assets ($432), current portion of operating lease liabilities ($158) and operating lease liabilities – net of current portion ($274) in the accompanying condensed consolidated balance sheet at December 31, 2019, have been reclassified from other noncurrent assets, accrued expenses and other current liabilities and other noncurrent liabilities, respectively, to conform to current period presentation. Certain amounts in the accompanying condensed statement of consolidated cash flows have been reclassified to conform to current period presentation.
COVID-19	COVID-19 In March 2020, the World Health Organization declared the novel strain of coronavirus a global pandemic (“COVID-19”) and recommended containment and mitigation measures worldwide. The impact of COVID-19 and the related economic, business and market disruptions are evolving rapidly, and their effects are uncertain. As a result of COVID-19, the Company was required to temporarily close its operations at its North Huntingdon, Pennsylvania facility for the period from March 23 through March 30, 2020. In response to COVID-19, the Company has incurred incremental costs associated with protecting the health and safety of the Company’s global workforce, enhanced sanitization of the Company’s global operating facilities, and information technology capabilities for employees operating remotely. Beginning in March 2020, restrictions imposed by various governmental authorities on both domestic and international shipping and travel have caused a disruption to the timing of delivery and installation of the Company’s 3D printing machines, resulting in negative impacts to the Company’s financial position, results of operations and cash flows. The duration and severity of the outbreak and its long-term impact on the Company’s business are uncertain at this time. The Company is unable to predict the impact that COVID-19 will have on its future financial position, results of operations and cash flows.
Recently Accounting Pronouncements	Recently Issued Accounting Guidance The Company considers the applicability and impact of all Accounting Standards Updates (“ASUs”) issued by the Financial Accounting Standards Board (the “FASB”). Recently issued ASUs not listed below either were assessed and determined to be not applicable or are currently expected to have no impact on the consolidated financial statements of the Company. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments – Credit Losses.” This ASU added a new impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The CECL model applies to most debt instruments, trade receivables, lease receivables, financial guarantee contracts, and other loan commitments. The CECL model does not have a minimum threshold for recognition of impairment losses and entities will need to measure expected credit losses on assets that have a low risk of loss. As a smaller reporting company pursuant to Rule 12b-2 of the Securities Exchange Act of 1934, as amended, these changes become effective for the Company on January 1, 2023. Management is currently evaluating the potential impact of these changes on the consolidated financial statements of the Company.
Loss Per Share	The Company presents basic and diluted loss per common share amounts. Basic loss per common share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares outstanding during the applicable period. Diluted loss per common share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares and common equivalent shares outstanding during the applicable period.
Revenue	The Company derives revenue from the sale of 3D printing machines and 3D printed and other products, materials and services. Revenue is recognized when the Company satisfies its performance obligation(s) under a contract (either implicit or explicit) by transferring the promised product or service to a customer either when (or as) the customer obtains control of the product or service. A performance obligation is a promise in a contract to transfer a distinct product or service to a customer. A contract’s transaction price is allocated to each distinct performance obligation. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring products or providing services. As such, revenue is recorded net of returns, allowances, customer discounts, and incentives. Sales, value add, and other taxes collected from customers and remitted to governmental authorities are accounted for on a net (excluded from revenue) basis. Shipping and handling costs are included in cost of sales. Certain of the Company’s contracts with customers provide for multiple performance obligations. Sales of 3D printing machines may also include optional equipment, materials, replacement components and services (installation, training and other services, including maintenance services and/or an extended warranty). Certain other cont r acts have a single performance obligation, as the promise to transfer products or services is not separately identifiable from other promises in the contract and, therefore, not distinct. For contracts with multiple performance obligations, the Company allocates the contract’s transaction price to each performance obligation using the Company’s best estimate of stand-alone selling price for each distinct product or service in the contract, which is generally based on an observable price.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
Accumulated Other Comprehensive Loss (Tables)	Sep. 30, 2020
Equity [Abstract]
Summary of Changes in the Components of Accumulated Other Comprehensive Loss	The following table summarizes changes in the components of accumulated other comprehensive loss for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Foreign currency translation adjustments Balance at beginning of period $ (11,951 ) $ (10,941 ) $ (11,483 ) $ (10,748 ) Other comprehensive income (loss) 856 (1,387 ) 388 (1,580 ) Balance at end of period $ (11,095 ) $ (12,328 ) $ (11,095 ) $ (12,328 )

Loss Per Share (Tables)

Loss Per Share (Tables)	9 Months Ended
Loss Per Share (Tables)	Sep. 30, 2020
Earnings Per Share [Abstract]
Computation of Basic and Diluted Loss Per Common Share	The information used to compute basic and diluted net loss per common share was as follows for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Net loss $ (3,273 ) $ (4,844 ) $ (10,944 ) $ (13,129 ) Weighted average shares outstanding (basic and diluted) 17,596,076 16,332,974 16,812,806 16,296,554 Net loss per common share: Basic $ (0.19 ) $ (0.30 ) $ (0.65 ) $ (0.81 ) Diluted $ (0.19 ) $ (0.30 ) $ (0.65 ) $ (0.81 )

Revenue (Tables)

Revenue (Tables)	9 Months Ended
Revenue (Tables)	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Summary of Revenue by Product Group	The following table summarizes the Company’s revenue by product group for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 3D printing machines $ 10,488 $ 3,972 $ 21,703 $ 16,532 3D printed and other products, materials and services 6,911 6,912 20,178 19,210 $ 17,399 $ 10,884 $ 41,881 $ 35,742

Cash, Cash Equivalents, and R_2

Cash, Cash Equivalents, and Restricted Cash (Tables)	9 Months Ended
Cash, Cash Equivalents, and Restricted Cash (Tables)	Sep. 30, 2020
Cash And Cash Equivalents [Abstract]
Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash	The following provides a reconciliation of cash, cash equivalents, and restricted cash as reported in the accompanying condensed consolidated balance sheet to the same such amounts shown in the accompanying condensed statement of consolidated cash flows as of the dates indicated: September 30, December 31, 2020 2019 Cash and cash equivalents $ 39,428 $ 5,265 Restricted cash 508 978 Cash, cash equivalents, and restricted cash $ 39,936 $ 6,243

Inventories (Tables)

Inventories (Tables)	9 Months Ended
Inventories (Tables)	Sep. 30, 2020
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consisted of the following as of the dates indicated: September 30, December 31, 2020 2019 Raw materials and components $ 10,811 $ 8,841 Work in process 3,698 4,922 Finished goods 7,678 6,007 $ 22,187 $ 19,770
Summary of Changes in Allowance for Slow-moving and Obsolete Inventories	The following table summarizes changes in the allowance for slow-moving and obsolete inventories for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Balance at beginning of period $ 2,493 $ 4,149 $ 3,443 $ 4,143 Provision for slow-moving and obsolete inventories ̶ net 30 63 130 194 Reductions for sale, consumption or scrap of previously reserved amounts (55 ) (376 ) (1,110 ) (482 ) Foreign currency translation adjustments 94 (152 ) 99 (171 ) Balance at end of period $ 2,562 $ 3,684 $ 2,562 $ 3,684

Property and Equipment (Tables)

Property and Equipment (Tables)	9 Months Ended
Property and Equipment (Tables)	Sep. 30, 2020
Long Lived Assets [Abstract]
Summary of Property and Equipment	Property and equipment consisted of the following as of the dates indicated September 30, December 31, Economic Life 2020 2019 (in years) Land $ 3,436 $ 6,980 N/A Buildings and related improvements 10,141 25,675 5 - 40 Machinery and equipment 20,658 19,531 3 - 20 Other 6,193 7,086 3 - 20 40,428 59,272 Less: Accumulated depreciation (20,092 ) (21,478 ) 20,336 37,794 Construction-in-progress 588 1,101 Property and equipment ̶ net $ 20,924 $ 38,895

Product Warranty Reserves (Tabl

Product Warranty Reserves (Tables)	9 Months Ended
Product Warranty Reserves (Tables)	Sep. 30, 2020
Product Warranties Disclosures [Abstract]
Summary of Changes in Product Warranty Reserves	The following table summarizes changes in product warranty reserves, which amounts were reflected in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Balance at beginning of period $ 603 $ 1,223 $ 866 $ 1,670 Provisions for new issuances 391 182 854 711 Payments (561 ) (409 ) (1,406 ) (1,257 ) Reserve adjustments 607 (65 ) 728 (188 ) Foreign currency translation adjustments 25 (20 ) 23 (25 ) Balance at end of period $ 1,065 $ 911 $ 1,065 $ 911

Leases (Tables)

Leases (Tables)	9 Months Ended
Leases (Tables)	Sep. 30, 2020
Leases [Abstract]
Schedule of Future Minimum Lease Payments of Operating Leases Arrangements	Future minimum lease payments of operating lease arrangements (with initial terms greater than twelve months) : 2020 $ 510 2021 2,009 2022 1,973 2023 33 2024 12 Thereafter 2 Total minimum lease payments 4,539 Less: Present value discount (261 ) Total operating lease liabilities $ 4,278
Schedule of Supplemental Information Related to Operating Lease Arrangements	Supplemental information related to operating lease arrangements was as follows as of and for the nine months ended September 30, 2020: Operating lease right-of-use assets $ 4,278 Current portion of operating lease liabilities $ 1,843 Operating lease liabilities ̶ net of current portion $ 2,435 Right-of-use assets obtained in exchange for new operating lease liabilities $ 4,876 Cash paid for amounts included in the measurement of operating lease liabilities $ 1,472 Weighted average remaining lease term (in years) 2.3 Weighted average discount rate 5.1 %
Schedule of Operating and Sales-type Lease Arrangements	The Company recognized the following components under operating and sales-type lease arrangements in the accompanying condensed statement of consolidated operations and comprehensive loss for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Operating Sales- type Operating Sales- type Operating Sales- type Operating Sales- type Revenue $ 227 $ — $ 261 $ — $ 589 $ — $ 1,287 $ — Interest income (a) $ — $ 12 $ — $ 21 $ — $ 47 $ — $ 76
Schedule of Net Investment in Sales-type Leases	The Company’s net investment in sales-type leases consisted of the following as of the dates indicated: September 30, December 31, 2020 2019 Future minimum lease payments receivable $ 1,413 $ 1,595 Less: Allowance for doubtful accounts (443 ) (424 ) Net future minimum lease payments receivable 970 1,171 Less: Unearned interest income (177 ) (220 ) Net investment in sales-type leases $ 793 $ 951
Schedule of Future Minimum Lease Payment Receivable of Non-Cancellable Operating and Sales-type Lease	Future minimum lease payments of non-cancellable operating and sales-type lease arrangements as of September 30, 2020 were as follows: Operating Sales-type 2020 $ 216 $ 226 2021 273 385 2022 — 385 2023 — 417 2024 — — Thereafter — — Total minimum lease payments $ 489 $ 1,413 Less: Allowance for doubtful accounts (443 ) Less: Present value discount (177 ) Future minimum lease payments receivable $ 793

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
Long-Term Debt (Tables)	Sep. 30, 2020
Debt Disclosure [Abstract]
Components of Long-Term Debt	September 30, 2020 December 31, 2019 Principal Unamortized Debt Issuance Costs Net Principal Unamortized Debt Issuance Costs Net Paycheck Protection Program loan $ 2,194 $ — $ 2,194 $ — $ — $ — Building note payable 1,266 (16 ) 1,250 1,384 (20 ) 1,364 Less: Amount due within one year (1,500 ) 4 (1,496 ) (157 ) 4 (153 ) $ 1,960 $ (12 ) $ 1,948 $ 1,227 $ (16 ) $ 1,211
Future Maturities of Long-Term Debt	Future maturities of long-term debt at September 30, 2020, were as follows: 2020 $ 282 2021 1,627 2022 668 2023 188 2024 195 Thereafter 500 $ 3,460

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
Income Taxes (Tables)	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Reconciliation of Unrecognized Tax Benefits (Including Accrued Interest and Penalties)	A reconciliation of the beginning and ending amount of unrecognized tax benefits (including accrued interest and penalties) was as follows for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Balance at beginning of period $ — $ 105 $ — $ 1,186 Additions based on tax positions related to the current year — — — — Additions for tax positions of prior years — 2 — 4 Reductions for tax positions of prior years — — — (1,075 ) Settlements — — — — Foreign currency translation adjustments — (5 ) — (13 ) Balance at end of period $ — $ 102 $ — $ 102

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	9 Months Ended
Equity-Based Compensation (Tables)	Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Equity-Based Compensation Expense	The following table summarizes the total equity-based compensation expense recognized by the Company for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Equity-based compensation expense recognized: Stock options $ 127 $ 195 $ 316 $ 511 Restricted stock 244 171 490 545 Other (a) 8 (371 ) 22 20 Total equity-based compensation expense before income taxes 379 (5 ) 828 1,076 Benefit for income taxes (b) — — — — Total equity-based compensation expense net of income taxes $ 379 $ (5 ) $ 828 $ 1,076 (a) For each of the 2020 periods, Other represents expense associated with certain employee contractual amounts to be settled in equity. For each of the 2019 periods, Other represents activity associated with the 2019 Program and certain employee contractual amounts to be settled in equity. (b) The Benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 based on recorded valuation allowances against net deferred tax assets.
Assumptions for Fair Value of Stock Options Granted Estimated on the Date of Grant Using the Black-Scholes Option	The fair value of stock options was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions for the periods indicated: Nine Months Ended September 30, 2020 2019 Weighted average fair value per stock option $5.11 - $6.20 $2.77 - $3.68 Volatility 58.0% - 58.6% 54.0% - 60.1% Average risk-free interest rate 0.2% 1.5% - 2.5% Dividend yield 0.0% 0.0% Expected term (years) 3.5 2.5 - 3.5
Summary of Activity for Stock Options	The activity for stock options was as follows for the periods indicated: Nine Months Ended September 30, 2020 2019 Number Options Weighted Exercise Price Weighted Average Grant Date Fair Value Number Options Weighted Exercise Price Weighted Average Grant Date Fair Value Outstanding at beginning of period 854,259 $ 9.34 $ 4.49 621,986 $ 10.66 $ 5.52 Stock options granted 25,022 $ 14.40 $ 5.99 290,610 $ 7.35 $ 2.95 Stock options exercised (117,854 ) $ 7.28 $ 3.12 (40,432 ) $ 7.17 $ 3.03 Stock options forfeited (79,936 ) $ 7.85 $ 3.41 (9,773 ) $ 7.67 $ 3.70 Stock options expired (26,874 ) $ 12.02 $ 6.78 (34,332 ) $ 16.87 $ 10.30 Outstanding at end of period 654,617 $ 9.81 $ 4.75 828,059 $ 9.44 $ 4.56 Exercisable at end of period 506,295 $ 10.46 $ 5.27 403,479 $ 11.30 $ 6.02 Expected to vest at end of period 148,322 $ 7.62 $ 3.01 424,580 $ 7.68 $ 3.18
Summary of Activity for Restricted Stock Awards	The activity for restricted stock was as follows for the periods indicated: Nine Months Ended September 30, 2020 2019 Shares of Restricted Stock Weighted Average Grant Date Fair Value Shares of Restricted Stock Weighted Average Grant Date Fair Value Outstanding at beginning of period 66,513 $ 8.76 67,001 $ 8.30 Restricted stock granted 209,891 $ 9.58 66,763 $ 8.98 Restricted stock vested (77,013 ) $ 8.94 (62,251 ) $ 8.65 Restricted stock forfeited — $ — (5,000 ) $ 6.75 Outstanding at end of period 199,391 $ 9.55 66,513 $ 8.76 Restricted stock expected to vest at end of period 199,391 $ 9.55 66,513 $ 8.76

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
Fair Value Measurements (Tables)	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Carrying Values and Fair Values of Other Financial Instruments	The carrying values and fair values of other financial instruments (assets and liabilities) not required to be recorded at fair value were as follows as of the dates indicated: September 30, December 31, 2020 2019 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 39,428 $ 39,428 $ 5,265 $ 5,265 Restricted cash $ 508 $ 508 $ 978 $ 978 Debt issuance costs (a) $ 120 $ — $ 107 $ — Current portion of long-term debt (b) $ 1,496 $ 1,365 $ 153 $ 157 Long-term debt ̶ (b) $ 1,948 $ 1,954 $ 1,211 $ 1,227 (a) Represents debt issuance costs associated with the Company’s related party revolving credit facility (Note 12) of which $35 and (b) Carrying values at September 30, 2020 and December 31, 2019 are net of unamortized debt issuance costs of $16 and $20, respectively

Other Expense (Income) - Net (T

Other Expense (Income) - Net (Tables)	9 Months Ended
Other Expense (Income) - Net (Tables)	Sep. 30, 2020
Other Income And Expenses [Abstract]
Schedule of Other Expense (Income) - Net	Other expense (income) – net consisted of the following for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Interest income $ (4 ) $ (2 ) $ (19 ) $ (10 ) Foreign currency losses (gains) - net 299 (136 ) 262 (85 ) Other – net 19 4 76 30 $ 314 $ (134 ) $ 319 $ (65 )

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Entity Incorporation, State or Country Code	DE
Date of incorporation	Jan. 1, 2013
Operating lease liabilities - net of current portion	$ 2,435	$ 274
Operating lease right-of-use assets	4,278	432
Current portion of operating lease liabilities	$ 1,843	$ 158
Subsidiary Guarantors [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Percentage of ownership in subsidiary guarantors	100.00%

Liquidity - Additional Informat

Liquidity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Apr. 18, 2020	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Net loss	$ (3,273)		$ (10,944)	$ (13,129)
Cash and cash equivalents	$ 39,428		39,428			$ 5,265
Sale of equity or debt instruments			$ 125,000
Sale of stock, number of shares issued in transaction	2,060,878
Sale of stock, price per share	$ 12.26		$ 12.26
Proceeds from stock plans	$ 24,512
Incurred expenses	124		$ 314
Unpaid incurred expenses	213		213
Unrestricted cash proceeds in connection with loan	2,194		2,194
Lender [Member] \| Paycheck Protection Program [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Unrestricted cash proceeds in connection with loan					$ 2,194
Accounts Payable [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Unpaid incurred expenses	147		147
Accrued Expenses and Other Current Liabilities [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Unpaid incurred expenses	$ 66		66
Initial And Secondary Public Offerings [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cumulative unrestricted net proceeds from common stock			$ 195,847
Equity Distribution Agreement Oppenheimer and Company [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sale of stock, consideration received on transaction		$ 25,000
Commission on sale of common stock		3.00%
Sale of stock, number of shares issued in transaction	1,822,274		2,204,875
Canaccord Equity Distribution Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sale of stock, consideration received on transaction			$ 25,000
Commission on sale of common stock	3.00%		3.00%
Sale of stock, number of shares issued in transaction	238,604		238,604
Oppenheimer and Canaccord Equity Distribution Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sale of stock, number of shares issued in transaction			2,443,479
Sale of stock, price per share	$ 11.73		$ 11.73
Proceeds from stock plans			$ 27,800
Revolving Credit Facility [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Related party revolving credit facility	$ 10,000		$ 10,000

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss - Summary of Changes in the Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Balance at beginning of period	$ (11,951)	$ (10,941)	$ (11,483)	$ (10,748)
Other comprehensive income (loss)	856	(1,387)	388	(1,580)
Balance at end of period	$ (11,095)	$ (12,328)	$ (11,095)	$ (12,328)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Accumulated other comprehensive loss, tax	$ 0	$ 0
Amounts reclassified to earnings from accumulated other comprehensive loss	$ 0	$ 0

Loss Per Share - Additional Inf

Loss Per Share - Additional Information (Detail) - shares	9 Months Ended
Loss Per Share - Additional Information (Detail) - shares	Sep. 30, 2020	Sep. 30, 2019
Stock Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares of anti-dilutive common stock	654,617	828,059
Restricted Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares of anti-dilutive common stock	199,391	66,513

Loss Per Share - Computation of

Loss Per Share - Computation of Basic and Diluted Loss Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net loss	$ (3,273)	$ (4,023)	$ (3,648)	$ (4,844)	$ (3,789)	$ (4,496)	$ (10,944)	$ (13,129)
Weighted average shares outstanding (basic and diluted)	17,596,076			16,332,974			16,812,806	16,296,554
Net loss per common share:
Basic	$ (0.19)			$ (0.30)			$ (0.65)	$ (0.81)
Diluted	$ (0.19)			$ (0.30)			$ (0.65)	$ (0.81)

Revenue - Summary of Revenue by

Revenue - Summary of Revenue by Product Group (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue from External Customer [Line Items]
Revenue	$ 17,399	$ 10,884	$ 41,881	$ 35,742
3D Printing Machines [Member]
Revenue from External Customer [Line Items]
Revenue	10,488	3,972	21,703	16,532
3D Printed and Other Products, Materials and Services [Member]
Revenue from External Customer [Line Items]
Revenue	$ 6,911	$ 6,912	$ 20,178	$ 19,210

Revenue - Additional Informatio

Revenue - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Revenue, description of payment terms			the Company’s terms of sale generally require payment within 30 to 60 days after delivery, although the Company also recognizes that longer payment periods are customary in certain countries where it transacts business.
Revenue recognized related to contract liabilities			$ 7,233
Revenue, remaining performance obligation	$ 42,600		42,600
Allowance for doubtful accounts	524		524		$ 508
(Recoveries) provision for bad debts ̶ net	$ 15	$ 414	$ (4)	$ 264
Maximum [Member]
Disaggregation Of Revenue [Line Items]
Term till payment is required from date of shipment			60 days
Minimum [Member]
Disaggregation Of Revenue [Line Items]
Term till payment is required from date of shipment			30 days

Revenue - Additional Informat_2

Revenue - Additional Information (Detail 1) $ in Thousands	Sep. 30, 2020USD ($)
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation	$ 42,600
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-07-01
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation	$ 35,500
Revenue, remaining performance obligation, Expected timing of satisfaction, period	12 months

Cash, Cash Equivalents, and R_3

Cash, Cash Equivalents, and Restricted Cash - Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Cash And Cash Equivalents [Abstract]
Cash and cash equivalents	$ 39,428	$ 5,265
Restricted cash	508	978
Cash, cash equivalents, and restricted cash	$ 39,936	$ 6,243

Cash, Cash Equivalents, and R_4

Cash, Cash Equivalents, and Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	$ 508	$ 978
United States Bank [Member]
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	$ 508	508
German Bank [Member]
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral		$ 470

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials and components	$ 10,811	$ 8,841
Work in process	3,698	4,922
Finished goods	7,678	6,007
Inventories	$ 22,187	$ 19,770

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Inventory [Line Items]
Allowance for slow-moving and obsolete inventories	$ 2,562	$ 2,493	$ 3,443	$ 3,684	$ 4,149	$ 4,143
Inventories [Member]
Inventory [Line Items]
Inventory (credit) charge	$ 205

Inventories - Summary of Change

Inventories - Summary of Changes in Allowance for Slow-moving and Obsolete Inventories (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Balance at beginning of period	$ 2,493	$ 4,149	$ 3,443	$ 4,143
Provision for slow-moving and obsolete inventories - net	30	63	130	194
Reductions for sale, consumption or scrap of previously reserved amounts	(55)	(376)	(1,110)	(482)
Foreign currency translation adjustments	94	(152)	99	(171)
Balance at end of period	$ 2,562	$ 3,684	$ 2,562	$ 3,684

Property and Equipment - Summar

Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 40,428	$ 59,272
Less: Accumulated depreciation	(20,092)	(21,478)
Property and equipment, excluding construction-in-progress	20,336	37,794
Construction-in-progress	588	1,101
Property and equipment ̶ net	20,924	38,895
Land [Member]
Property Plant And Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	3,436	6,980
Building and Related Improvements [Member]
Property Plant And Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 10,141	25,675
Building and Related Improvements [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property and equipment, Economic Life	5 years
Building and Related Improvements [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property and equipment, Economic Life	40 years
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 20,658	19,531
Machinery and Equipment [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property and equipment, Economic Life	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property and equipment, Economic Life	20 years
Other [Member]
Property Plant And Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 6,193	$ 7,086
Other [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property and equipment, Economic Life	3 years
Other [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property and equipment, Economic Life	20 years

Property and Equipment - Additi

Property and Equipment - Additional Information (Details)	3 Months Ended			9 Months Ended		12 Months Ended
Property and Equipment - Additional Information (Details)	Sep. 30, 2020USD ($)Asset_Group	Mar. 31, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)Asset_Group	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Long Lived Assets [Abstract]
Depreciation	$ 817,000		$ 1,142,000	$ 2,925,000	$ 3,491,000
Derecognized net property and equipment		$ 17,282,000
Gain on sale of facility		$ 1,462,000		$ 1,462,000
Number of operating asset groups \| Asset_Group	3			3
Long-lived assets held for use impairment loss				$ 0		$ 0

Product Warranty Reserves - Add

Product Warranty Reserves - Additional Information (Detail)	9 Months Ended
Product Warranty Reserves - Additional Information (Detail)	Sep. 30, 2020
Product Warranties Disclosures [Abstract]
Standard product warranty period	Substantially all of the Company’s 3D printing machines are covered by a standard one-year warranty. Generally, at the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty.

Product Warranty Reserves - Sum

Product Warranty Reserves - Summary of Changes in Product Warranty Reserves (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Guarantees [Abstract]
Balance at beginning of period	$ 603	$ 1,223	$ 866	$ 1,670
Provisions for new issuances	391	182	854	711
Payments	(561)	(409)	(1,406)	(1,257)
Reserve adjustments	607	(65)	728	(188)
Foreign currency translation adjustments	25	(20)	23	(25)
Balance at end of period	$ 1,065	$ 911	$ 1,065	$ 911

Leases - Additional Information

Leases - Additional Information (Detail) € in Thousands	Dec. 10, 2019USD ($)RenewalOption	Dec. 10, 2019EUR (€)RenewalOption	Dec. 30, 2019USD ($)	Dec. 30, 2019EUR (€)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 10, 2019EUR (€)
Leases [Line Items]
Lease expiration year							2026
Short term lease cost					$ 24,000	$ 44,000	$ 96,000	$ 156,000
Lease cost					527,000	$ 94,000	1,560,000	$ 305,000
Operating lease right-of-use asset					4,278,000		4,278,000		$ 432,000
Operating lease liability					$ 4,278,000		$ 4,278,000
Minimum [Member]
Leases [Line Items]
Operating lease arrangement terms					1 year		1 year
Maximum [Member]
Leases [Line Items]
Operating lease arrangement terms					5 years		5 years
Germany [Member] \| Purchase Agreement [Member] \| Sale-Leaseback of Gersthofen, Germany Facility [Member]
Leases [Line Items]
Purchase price from sale leaseback	$ 18,500,000									€ 17,000
Proceeds from sale leaseback			$ 2,200,000	€ 2,000
Sale leaseback annual rent	$ 1,700,000	€ 1,500
Sale leaseback transaction, lease terms							Concurrent with the execution of the Purchase Agreement, ExOne GmbH and the Buyer entered into a rental contract (the “Lease”) for the leaseback of the Facility for an initial aggregate annual rent totaling approximately $1,700 (€1,500), plus applicable taxes, which is fixed during the initial three-year term and is subject to adjustment on an annual basis (in accordance with the consumer price index for Germany) during the two five-year option extension periods.
Sale leaseback, term of contract	3 years	3 years
Number of renewal option for sale leaseback \| RenewalOption	2	2
Sale lease back renewal term	5 years	5 years
Sale-leaseback transaction closed date	February 18, 2020	February 18, 2020
Operating lease right-of-use asset	$ 4,605
Operating lease liability	$ 4,605
Related Parties Under Common Control [Member]
Leases [Line Items]
Short term lease cost					$ 4,000		$ 28,000

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Lease Payments of Operating Leases Arrangements (Detail) $ in Thousands	Sep. 30, 2020USD ($)
Leases [Abstract]
2020	$ 510
2021	2,009
2022	1,973
2023	33
2024	12
Thereafter	2
Total minimum lease payments	4,539
Less: Present value discount	(261)
Total operating lease liabilities	$ 4,278

Leases - Schedule of Supplement

Leases - Schedule of Supplemental Information Related to Operating Lease Arrangements (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease right-of-use assets	$ 4,278	$ 432
Current portion of operating lease liabilities	1,843	158
Operating lease liabilities ̶ net of current portion	2,435	$ 274
Right-of-use assets obtained in exchange for new operating lease liabilities	4,876
Cash paid for amounts included in the measurement of operating lease liabilities	$ 1,472
Weighted average remaining lease term (in years)	2 years 3 months 18 days
Weighted average discount rate	5.10%

Leases - Schedule of Operating

Leases - Schedule of Operating and Sales-type Lease Arrangements (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Leases [Abstract]
Operating lease revenue		$ 227	$ 261	$ 589	$ 1,287
Sales-type lease interest income	[1]	$ 12	$ 21	$ 47	$ 76

[1]	Interest income relating to sales-type leases is recorded as a component of revenue in the accompanying condensed statement of consolidated operations and comprehensive loss for each of the periods presented.

Leases - Schedule of Net Invest

Leases - Schedule of Net Investment in Sales-type Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Leases [Abstract]
Future minimum lease payments receivable	$ 1,413
Less: Allowance for doubtful accounts	(443)
Net future minimum lease payments receivable	970
Less: Unearned interest income	(177)
Net investment in sales-type leases	$ 793
Future minimum lease payments receivable		$ 1,595
Less: Allowance for doubtful accounts		(424)
Net future minimum lease payments receivable		1,171
Less: Unearned interest income		(220)
Net investment in sales-type leases		$ 951

Leases - Schedule of Future M_2

Leases - Schedule of Future Minimum Lease Payment Receivable of Non-Cancellable Operating and Sales-type Lease (Details) $ in Thousands	Sep. 30, 2020USD ($)
Operating lease arrangements
2020	$ 216
2021	273
Total minimum lease payments	489
Sales-type lease arrangements
2020	226
2021	385
2022	385
2023	417
Total minimum lease payments	1,413
Less: Allowance for doubtful accounts	(443)
Less: Present value discount	(177)
Future minimum lease payments receivable	$ 793

Contingencies and Commitments -

Contingencies and Commitments - Additional Information (Detail) - Amended GmbH Credit Agreement [Member] - Financial Guarantees and Letters of Credit [Member] € in Thousands, $ in Thousands	Feb. 24, 2020USD ($)	Feb. 24, 2020EUR (€)	Sep. 30, 2020USD ($)	Sep. 30, 2020EUR (€)	Dec. 31, 2019USD ($)	Dec. 31, 2019EUR (€)
Line Of Credit Facility [Line Items]
Line of credit facility, increased capacity amount	$ 4,100	€ 3,500
German Bank [Member]
Line Of Credit Facility [Line Items]
Credit facility, outstanding amount			$ 583	€ 497	$ 560	€ 499
Debt expiration dates range start			Oct. 31, 2020
Debt expiration dates range end			Feb. 28, 2023
Minimum [Member] \| German Bank [Member]
Line Of Credit Facility [Line Items]
Issuance of financial guarantees and letters of credit	1,200	1,000
Maximum [Member] \| Cash Collateral [Member] \| German Bank [Member]
Line Of Credit Facility [Line Items]
Issuance of financial guarantees and letters of credit	$ 1,200	€ 1,000

Related Party Revolving Credit

Related Party Revolving Credit Facility - Additional Information (Detail) - USD ($)	Feb. 18, 2020	Mar. 12, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Amortization of debt issuance costs					$ 39,000	$ 70,000
Revolving Credit Facility [Member]
Related Party Transaction [Line Items]
Line of credit facility, maximum borrowing capacity			$ 10,000,000		10,000,000
Interest expense relating to the Credit Agreement				$ 65,000		165,000
Revolving Credit Facility [Member] \| Prepaid Expenses and Other Current Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			35,000		35,000		$ 88,000
Revolving Credit Facility [Member] \| Other Noncurrent Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			$ 85,000		$ 85,000		$ 19,000
Revolving Credit Facility [Member] \| LBM Holdings, LLC [Member]
Related Party Transaction [Line Items]
Line of credit facility, maximum borrowing capacity		$ 15,000,000
Credit facility, expiration period		3 years
Credit facility, expiration date		Mar. 12, 2021
Credit facility, description of variable rate basis					one-month LIBOR
Credit facility, interest rate			5.10%		5.10%		6.80%
Credit facility, commitment fee on unused portion, percentage		0.75%
Credit facility, commitment fee on unused portion, payable term					The Credit Agreement required a commitment fee of 75 basis points, or 0.75%, on the unused portion of the facility, payable monthly in arrears
Credit facility, up-front commitment fee percentage		1.25%
Credit facility, up-front commitment fee amount		$ 188,000
Credit facility, minimum increments		$ 1,000,000
Credit facility, borrowings			$ 0	$ 0	$ 0	$ 0
Credit facility, outstanding amount			0		0		$ 0
Debt issuance costs, gross			265,000		265,000
Interest expense relating to the Credit Agreement			34,000		113,000
Amortization of debt issuance costs			8,000		35,000
Debt issuance costs, net			120,000		120,000
Interest expense related to commitment fee			26,000		78,000
Accounts payable			8,000		8,000		$ 28,000
Revolving Credit Facility [Member] \| LBM Holdings, LLC [Member] \| Prepaid Expenses and Other Current Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			35,000		35,000
Revolving Credit Facility [Member] \| LBM Holdings, LLC [Member] \| Other Noncurrent Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			85,000		85,000
Revolving Credit Facility [Member] \| LBM Holdings, LLC [Member] \| London Interbank Offered Rate (LIBOR)
Related Party Transaction [Line Items]
Credit facility, basis spread on variable rate		5.00%
Amended Revolving Credit Facility [Member] \| LBM Holdings, LLC [Member]
Related Party Transaction [Line Items]
Line of credit facility, maximum borrowing capacity	$ 10,000,000
Credit facility, expiration date	Mar. 31, 2024
Credit facility, commitment fee on unused portion, percentage	1.00%
Debt issuance costs, gross			$ 49,000		$ 49,000

Long-Term Debt - Components of

Long-Term Debt - Components of Long-Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Paycheck Protection Program loan, Principal	$ 2,194
Building note payable, Principal	1,266	$ 1,384
Less: amount due within one year, Principal	(1,500)	(157)
Long-term debt - net of current portion, Principal	1,960	1,227
Building note payable, Unamortized Debt Issuance Costs	(16)	(20)
Less: amount due within one year, Unamortized Debt Issuance Costs	4	4
Long-term debt - net of current portion, Unamortized Debt Issuance Costs	(12)	(16)
Paycheck Protection Program loan, Net	2,194
Building note payable, Net	1,250	1,364
Less: amount due within one year, Net	(1,496)	(153)
Long-term debt ̶ net of current portion	$ 1,948	$ 1,211

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($) $ in Thousands	Apr. 18, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Loan principal amount		$ 2,194
Building Note Payable [Member]
Debt Instrument [Line Items]
Notes payable monthly payments		$ 18
Building note payable, with monthly payments interest rate		4.00%
Building note payable, with monthly payments basis spread		3.25%
Date of interest rate adjustment		2017-05
Notes payable maturity		2027-05
Building Note Payable [Member] \| Building [Member] \| North Huntington, Pennsylvania [Member]
Debt Instrument [Line Items]
Carrying value of collateralized facility		$ 4,838
United States Treasury Securities [Member] \| Building Note Payable [Member]
Debt Instrument [Line Items]
Notes payable monthly payments		$ 19
Paycheck Protection Program [Member]
Debt Instrument [Line Items]
Loan bears interest rate	1.00%
Maturity date	Apr. 18, 2022
Lender [Member] \| Paycheck Protection Program [Member]
Debt Instrument [Line Items]
Loan principal amount	$ 2,194

Long-Term Debt - Future Maturit

Long-Term Debt - Future Maturities of Long-Term Debt (Detail) $ in Thousands	Sep. 30, 2020USD ($)
Debt Disclosure [Abstract]
2020	$ 282
2021	1,627
2022	668
2023	188
2024	195
Thereafter	500
Long-term debt	$ 3,460

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
Income Taxes - Additional Information (Detail) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2019
Schedule Of Income Taxes [Line Items]
Provision (benefit) for income taxes	$ (34,000)	$ 15,000	$ 200,000	$ (686,000)
Effective tax rate	1.00%	0.30%	1.90%	5.00%
United States statutory rate	21.00%	21.00%	21.00%	21.00%
Penalties and interest expense	$ 0	$ 0	$ 0	$ 0
Subsidiaries [Member] \| Local Taxing Authorities [Member] \| Germany [Member]
Schedule Of Income Taxes [Line Items]
Reversal of previously recorded liabilities for uncertain tax positions					$ 1,075,000
Uncertain tax positions expected amount to be offset against net operating loss carryforwards					$ 257,000

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Including Accrued Interest and Penalties) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 105	$ 1,186
Additions for tax positions of prior years	2	4
Reductions for tax positions of prior years		(1,075)
Foreign currency translation adjustments	(5)	(13)
Balance at end of period	$ 102	$ 102

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Detail) - USD ($)	Jan. 24, 2013	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		$ 379,000		$ (5,000)			$ 828,000	$ 1,076,000
Weighted-average remaining vesting period							2 years 3 months 18 days
Proceeds from exercise of employee stock options							$ 858,000	$ 289,000
Incentive stock options exercised							117,854	40,432
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		127,000		195,000			$ 316,000	$ 511,000
Total future compensation expense		387,000					387,000
Intrinsic value, stock options exercisable		1,479,000					1,479,000
Intrinsic value, stock options expected to vest		705,000					$ 705,000
Weighted average remaining contractual term of stock options exercisable							3 years 3 months 18 days
Weighted average remaining contractual term of stock options expected to vest							4 years
Intrinsic value of stock options exercised							$ 1,096,000	358,000
Proceeds from exercise of employee stock options							858,000	289,000
Income tax benefit							0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		244,000		$ 171,000			490,000	545,000
Total future compensation expense		$ 1,664,000					1,664,000
Fair value of restricted shares vested							635,000	535,000
Fair value of shares withtheld							$ 15,000	$ 68,000
Maximum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							3 years
Stock options contractual expiration period							10 years
Maximum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							3 years
Minimum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							1 year
Stock options contractual expiration period							5 years
Minimum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							1 year
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive stock options exercised		44,000	73,000	4,000	13,000	23,000
2013 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	500,000
Remaining shares available for future issuance		495,804					495,804
2013 Equity Incentive Plan [Member] \| Common Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares of common stock	3.00%
Number of Shares authorized	1,992,241
2019 Annual Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense, net reversal				$ 376,000
2020 Annual Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		$ 0					$ 0

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Equity-Based Compensation Expense (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		$ 379	$ (5)	$ 828	$ 1,076
Benefit for income taxes	[1]	0	0	0	0
Total equity-based compensation expense net of income taxes		379	(5)	828	1,076
Stock Options [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		127	195	316	511
Restricted Stock [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		244	171	490	545
Other [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes	[2]	$ 8	$ (371)	$ 22	$ 20

[1]	The Benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 based on recorded valuation allowances against net deferred tax assets.
[2]	For each of the 2020 periods, Other represents expense associated with certain employee contractual amounts to be settled in equity. For each of the 2019 periods, Other represents activity associated with the 2019 Program and certain employee contractual amounts to be settled in equity.

Equity-Based Compensation - S_2

Equity-Based Compensation - Summary of Equity-Based Compensation Expense (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Benefit for income taxes from equity-based compensation	[1]	$ 0	$ 0	$ 0	$ 0

[1]	The Benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 based on recorded valuation allowances against net deferred tax assets.

Equity-Based Compensation - Ass

Equity-Based Compensation - Assumptions for Fair Value of Stock Options Granted Estimated on the Date of Grant Using the Black-Scholes Option (Detail) - Stock Options [Member] - $ / shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average risk-free interest rate	0.20%
Dividend yield	0.00%	0.00%
Expected term (years)	3 years 6 months
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option	$ 5.11	$ 2.77
Volatility	58.00%	54.00%
Average risk-free interest rate		1.50%
Expected term (years)		2 years 6 months
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option	$ 6.20	$ 3.68
Volatility	58.60%	60.10%
Average risk-free interest rate		2.50%
Expected term (years)		3 years 6 months

Equity-Based Compensation - S_3

Equity-Based Compensation - Summary of Activity for Stock Options (Detail) - $ / shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock options outstanding, Beginning balance	854,259	621,986
Stock options granted	25,022	290,610
Stock options exercised	(117,854)	(40,432)
Stock options forfeited	(79,936)	(9,773)
Stock options expired	(26,874)	(34,332)
Stock options outstanding, Ending balance	654,617	828,059
Exercisable at end of period	506,295	403,479
Expected to vest at end of period	148,322	424,580
Weighted average exercise price, Beginning balance	$ 9.34	$ 10.66
Weighted average exercise price, Stock options granted	14.40	7.35
Weighted average exercise price, Stock options exercised	7.28	7.17
Weighted average exercise price, Stock options forfeited	7.85	7.67
Weighted average exercise price, Stock options expired	12.02	16.87
Weighted average exercise price, Ending balance	9.81	9.44
Weighted average exercise price, Exercisable	10.46	11.30
Weighted average exercise price, Expected to vest, net of forfeitures	7.62	7.68
Weighted average grant date fair value, Beginning balance	4.49	5.52
Weighted average grant date fair value, Stock options granted	5.99	2.95
Weighted average grant date fair value, Stock options exercised	3.12	3.03
Weighted average grant date fair value, Stock options forfeited	3.41	3.70
Weighted average grant date fair value, Stock options expired	6.78	10.30
Weighted average grant date fair value, Ending balance	4.75	4.56
Weighted average grant date fair value, Exercisable	5.27	6.02
Weighted average grant date fair value, Expected to vest, net of forfeitures	$ 3.01	$ 3.18

Equity-Based Compensation - S_4

Equity-Based Compensation - Summary of Activity for Restricted Stock Awards (Detail) - Restricted Stock [Member] - $ / shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Restricted Shares, outstanding, Beginning Balance	66,513	67,001
Number of Restricted Shares, granted	209,891	66,763
Number of Restricted Shares, vested	(77,013)	(62,251)
Number of Restricted Shares, forfeited	0	(5,000)
Number of Restricted Shares, outstanding, Ending Balance	199,391	66,513
Number of Restricted Shares, expected to vest	199,391	66,513
Weighted Average Grant Date Fair Value, Beginning Balance	$ 8.76	$ 8.30
Weighted Average Grant Date Fair Value, granted	9.58	8.98
Weighted Average Grant Date Fair Value, vested	8.94	8.65
Weighted Average Grant Date Fair Value, forfeited	0	6.75
Weighted Average Grant Date Fair Value, Ending Balance	9.55	8.76
Weighted Average Grant Date Fair Value, expected to vest	$ 9.55	$ 8.76

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	Sep. 30, 2020	Apr. 18, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments (assets or liabilities) measured at fair value	$ 0		$ 0
Paycheck Protection Program [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan bears interest rate		1.00%

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Values and Fair Values of Other Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 39,428	$ 5,265
Restricted cash	508	978
Debt issuance costs	120	107
Current portion of long-term debt	1,496	153
Long-term debt ̶ net of current portion	1,948	1,211
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	39,428	5,265
Restricted cash	508	978
Current portion of long-term debt	1,365	157
Long-term debt ̶ net of current portion	$ 1,954	$ 1,227

Fair Value Measurements - Car_2

Fair Value Measurements - Carrying Values and Fair Values of Other Financial Instruments (Parenthetical) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt issuance costs	$ 16	$ 20
Revolving Credit Facility [Member] \| Prepaid Expenses and Other Current Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	35	88
Revolving Credit Facility [Member] \| Other Noncurrent Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	$ 85	$ 19

Concentration of Credit Risk -

Concentration of Credit Risk - Additional Information (Detail) - Five Most Significant Customers [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Revenue, Major Customer [Line Items]
Accounts receivable from significant customers	$ 1,291		$ 1,291		$ 3,230
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Revenue, Major Customer [Line Items]
Revenue concentration, by most significant customers	39.50%	30.20%	20.00%	23.80%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Purchases from related parties	$ 0		$ 0
Amounts due to related party	$ 0		0		$ 0
3D Printing Machines [Member]
Related Party Transaction [Line Items]
Purchases from related parties			30,000
Chairman of the Board of Directors [Member]
Related Party Transaction [Line Items]
Purchases from related parties		$ 5,000		$ 63,000
Fair market value of benefits received			$ 3,000

Other Expense (Income) - Net -

Other Expense (Income) - Net - Schedule of Other Expense (Income) - Net (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Other Income And Expenses [Abstract]
Interest income	$ (4)	$ (2)	$ (19)	$ (10)
Foreign currency losses (gains) - net	299	(136)	262	(85)
Other – net	19	4	76	30
Other expense - net	$ 314	$ (134)	$ 319	$ (65)