Zynex (ZYXI) 10-K27 Feb 202019 FY Annual reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2019	Feb. 27, 2020	Jun. 30, 2019
Document and Entity Information [Abstract]
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Entity Registrant Name	ZYNEX INC
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 291.7
Entity Common Stock, Shares Outstanding		32,811,832
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Central Index Key	0000846475
Amendment Flag	false
Trading Symbol	ZYXI

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash	$ 14,040,000	$ 10,128,000
Accounts receivable	5,833,000	2,791,000
Inventory, net	2,378,000	837,000
Prepaid expenses and other	315,000	568,000
Total current assets	22,566,000	14,324,000
Property and equipment, net	858,000	819,000
Operating lease asset	3,831,000	3,050,000
Finance lease asset	180,000	19,000
Deposits	329,000	314,000
Long term deferred income taxes	513,000	725,000
Total assets	28,277,000	19,251,000
Current liabilities:
Accounts payable and accrued expenses	2,133,000	1,552,000
Lease liability - operating leases	1,211,000	671,000
Lease liability - finance leases	45,000	14,000
Income taxes payable	52,000	688,000
Dividends payable	8,000	2,270,000
Accrued payroll and related taxes	1,748,000	908,000
Deferred insurance reimbursement	0	880,000
Total current liabilities	5,197,000	6,983,000
Long-term liabilities:
Lease liability - operating leases	3,282,000	2,967,000
Lease liability - finance leases	145,000	10,000
Total liabilities	8,624,000	9,960,000
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized; no shares issued and outstanding as of December 31, 2019 and December 31, 2018	0	0
Common stock, $0.001 par value; 100,000,000 shares authorized; 33,862,885 issued and 32,791,665 outstanding as of December 31, 2019 and 33,290,587 issued and 32,271,367 outstanding as of December 31, 2018	34,000	34,000
Additional paid-in capital	9,198,000	8,157,000
Treasury stock 1,071,220 and 1,019,220 shares, at December 31, 2019 and December 31, 2018, respectively, at cost	(3,846,000)	(3,675,000)
Retained earnings	14,356,000	4,864,000
Total Zynex, Inc. stockholders' equity	19,742,000	9,380,000
Non-controlling interest	(89,000)	(89,000)
Total stockholders' equity	19,653,000	9,291,000
Total liabilities and stockholders' equity	$ 28,277,000	$ 19,251,000

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
CONSOLIDATED BALANCE SHEETS
Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Shares, Issued	33,862,885	33,290,587
Common Stock, Shares, Outstanding	32,791,665	32,271,367
Treasury Stock, Shares	1,071,220	1,019,220

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
NET REVENUE
Total net revenue	$ 45,472	$ 31,917
COSTS OF REVENUE AND OPERATING EXPENSES
Costs of revenue - devices and supplies	8,814	6,038
Sales and marketing	14,016	6,503
General and administrative	11,576	9,006
Total costs of revenue and operating expenses	34,406	21,547
Income from operations	11,066	10,370
Other income/(expense)
Deferred insurance reimbursement	880
Interest income/(expense)	(5)	(154)
Other income/(expense), net	875	(154)
Income from operations before income taxes	11,941	10,216
Income tax expense	2,449	664
Net income	$ 9,492	$ 9,552
Net income per share:
Basic	$ 0.29	$ 0.29
Diluted	$ 0.28	$ 0.28
Weighted average basic shares outstanding	32,439	32,503
Weighted average diluted shares outstanding	33,963	34,043
Devices [Member]
NET REVENUE
Total net revenue	$ 10,713	$ 6,822
Supplies [Member]
NET REVENUE
Total net revenue	$ 34,759	$ 25,095

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 9,492	$ 9,552
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	778	448
Deferred insurance reimbursement	(880)
Inventory reserve	185
Lease incentive received		214
Amortization of debt issuance costs		153
Stock-based compensation	820	370
Gain on disposal of property and equipment		3
Provision for deferred income taxes	212	(725)
Change in operating assets and liabilities:
Accounts receivable	(3,042)	(660)
Prepaid and other assets	255	(372)
Accounts payable and other accrued liabilities	785	409
Inventory	(2,360)	(414)
Deposits	(15)	55
Other long-term obligations	73	375
Net cash provided by operating activities	6,303	9,408
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	(160)	(1,082)
Net cash used in investing activities	(160)	(1,082)
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal payments on subordinated debt		(384)
Payments on finance lease obligations	(19)	(123)
Common stock cash dividends	(2,262)
Purchase of treasury stock	(171)	(3,432)
Proceeds from the issuance of common stock	221	176
Net cash used in financing activities	(2,231)	(3,763)
Net increase in cash and cash equivalents	3,912	4,563
Cash and cash equivalents at beginning of period	10,128	5,565
Cash and cash equivalents at end of period	14,040	10,128
Supplemental disclosure of cash flow information:
Cash paid for income taxes	(2,873)	(772)
Cash paid for interest	(5)	(12)
Cash paid for rent	(956)	(394)
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use assets obtained in exchange for new operating lease liabilities	1,605	3,642
Right-of-use assets obtained in exchange for new finance lease liabilities	186
Inventory transferred to property and equipment under lease	$ 652
Lease incentive received		213
Common stock dividend declared and unpaid		$ 2,270

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Non-Controlling Interest	Total
Balance at Dec. 31, 2017	$ 33	$ 7,612	$ (243)	$ (2,411)	$ (89)	$ 4,902
Balance (in shares) at Dec. 31, 2017	32,778,040
Opening balance adjustment - ASC 842				(7)		(7)
Exercised and vested stock-based awards	$ 1	175				176
Exercised and vested stock-based awards (in shares)	425,710
Stock-based compensation expense		370				370
Treasury stock			(3,432)			(3,432)
Treasury stock (in shares)	(932,383)
Common stock dividends declared				(2,270)		(2,270)
Net income				9,552		9,552
Balance at Dec. 31, 2018	$ 34	8,157	(3,675)	4,864	(89)	9,291
Balance (in shares) at Dec. 31, 2018	32,271,367
Exercised and vested stock-based awards		221				221
Exercised and vested stock-based awards (in shares)	531,940
Warrant exercises (in shares)	40,366
Stock-based compensation expense		820				820
Treasury stock			(171)			(171)
Treasury stock (in shares)	(52,000)
Other (in shares)	(8)
Net income				9,492		9,492
Balance at Dec. 31, 2019	$ 34	$ 9,198	$ (3,846)	$ 14,356	$ (89)	$ 19,653
Balance (in shares) at Dec. 31, 2019	32,791,665

ORGANIZATION, NATURE OF BUSINES

ORGANIZATION, NATURE OF BUSINESS AND MANAGEMENT'S PLANS	12 Months Ended
ORGANIZATION, NATURE OF BUSINESS AND MANAGEMENT'S PLANS	Dec. 31, 2019
ORGANIZATION, NATURE OF BUSINESS AND MANAGEMENT'S PLANS
ORGANIZATION, NATURE OF BUSINESS AND MANAGEMENT'S PLANS	(1) ORGANIZATION, NATURE OF BUSINESS AND MANAGEMENT’S PLANS Organization Zynex, Inc. (a Nevada corporation) has its headquarters in Englewood, Colorado. We operate in one primary business segment, medical devices which include electrotherapy and pain management products. As of December 31, 2019, the Company’s only active subsidiary is Zynex Medical, Inc. (“ZMI,” a wholly-owned Colorado corporation) through which the Company conducts most of its operations. One other subsidiary, Zynex Europe, ApS (“ZEU,” a wholly-owned Denmark corporation), did not generate material revenues during the years ended December 31, 2019 and 2018 from international sales and marketing. Zynex Monitoring Solutions, Inc. (“ZMS,” a wholly-owned Colorado corporation) has developed a blood volume monitoring device but is awaiting approval by the U.S. Food and Drug Administration (“FDA”) as well as CE Marking in Europe; therefore, ZMS has achieved no revenues to date. Its inactive subsidiaries include Zynex NeuroDiagnostics, Inc. (“ZND,” a wholly-owned Colorado corporation), Zynex Billing and Consulting, LLC (“ZBC,” an 80% owned Colorado limited liability company) and Pharmazy, Inc. (“Pharmazy”), which was incorporated in June 2015 as a wholly-owned Colorado corporation. The Company’s compound pharmacy operated as a division of ZMI dba as Pharmazy through January 2016. The term “the Company” refers to Zynex, Inc. and its active and inactive subsidiaries. Nature of Business The Company designs, manufactures and markets medical devices that treat chronic and acute pain, as well as activate and exercise muscles for rehabilitative purposes with electrical stimulation. The Company’s devices are intended for pain management to reduce reliance on drugs and medications and provide rehabilitation and increased mobility through the utilization of non-invasive muscle stimulation, electromyography technology, interferential current (“IFC”), neuromuscular electrical stimulation (“NMES”) and transcutaneous electrical nerve stimulation (“TENS”). All our medical devices are designed to be patient friendly and designed for home use. Our devices are small, portable, battery operated and include an electrical pulse generator which is connected to the body via electrodes. All of our medical devices are marketed in the U.S. and are subject to FDA regulation and approval. Our products require a physician’s prescription before they can be dispensed in the U.S. Our primary product is the NexWave device. The NexWave is marketed to physicians and therapists by our field sales representatives. The NexWave requires consumable supplies, such as electrodes and batteries, which are shipped to patients on a recurring monthly basis, as needed. During the years ended December 31, 2019 and 2018, the Company generated substantially all of its revenue (99.99%) in North America from sales and supplies of its devices to patients and health care providers.

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
SIGNIFICANT ACCOUNTING POLICIES	Dec. 31, 2019
SIGNIFICANT ACCOUNTING POLICIES
SIGNIFICANT ACCOUNTING POLICIES	(2) SIGNIFICANT ACCOUNTING POLICIES Principles of Consolidation The accompanying consolidated financial statements include the accounts of Zynex, Inc. and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Non-controlling Interest Non-controlling interest in the equity of a subsidiary is accounted for and reported as a decrease in shareholders’ equity. Non-controlling interest represents the 20% ownership in the Company’s majority-owned inactive subsidiary, ZBC. Reclassifications During 2019, the Company began reporting costs related to its selling and marketing activities separate from its general and administrative costs. As a result, reclassifications between selling and marketing costs and general and administrative costs have been made to the results of operations for the year ended December 31, 2018 to conform to the consolidated 2019 financial statement presentation. These reclassifications had no effect on net earnings, retained earnings or cash flows as previously reported. Use of Estimates Preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. The most significant management estimates used in the preparation of the accompanying consolidated financial statements are associated with the allowance for billing adjustments and uncollectible accounts receivable, inventory reserves, the life of its leased devices, stock-based compensation, and valuation of long-lived assets and realizability of deferred tax assets. Fair Value of Financial Instruments The Company’s financial instruments include cash, accounts receivable, accounts payable, and accrued liabilities, for which current carrying amounts approximate fair value due to their short-term nature. Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. Short-term investments include investments with maturities greater than three months, but not exceeding 12 months, or highly liquid investments with maturities greater than 12 months that the Company intends to liquidate during the next 12 months for working capital needs. Inventory Inventories are stated at the lower of cost and net realizable value. Cost is computed using standard costs, which approximates actual costs on an average cost basis. Following are the components of inventory as of December 31, 2019 and 2018 (in thousands): December 31, 2019 December 31, 2018 Raw Materials $ 953 $ 454 Work-in-process 200 55 Finished Goods 1,640 576 $ 2,793 1,085 Less: reserve (415) (248) $ 2,378 $ 837 The Company monitors inventory for turnover and obsolescence and records losses for excess and obsolete inventory, as appropriate. The Company provides reserves for estimated excess and obsolete inventories equal to the difference between the costs of inventories on hand and the estimated market value based upon assumptions about future demand. If future demand is less favorable than currently projected by management, additional inventory write-downs may be required. Property and Equipment Property and equipment is recorded at cost. Repairs and maintenance expenditures are charged to expense as incurred. We compute depreciation expense on a straight-line basis over the estimated useful lives of the assets as follows: Classification Estimated Useful Life Office furniture and equipment 5 to 7 years Assembly equipment 7 years Vehicles 5 years Leasehold improvements Term of lease Leased devices 9 months Leases The Company determines if an arrangement is a lease at inception or modification of a contract. The Company recognizes finance and operating lease right-of-use assets and liabilities at the lease commencement date based on the estimated present value of the lease payments over the lease term. For our finance leases, the Company uses the implicit rate to determine the present value of future lease payments. For our operating leases that do not provide an implicit rate, the Company uses incremental borrowing rates to determine the present value of future lease payments. The Company includes options to extend or terminate a lease in the lease term when it is reasonably certain to exercise such options. The Company recognizes leases with an initial term of 12 months or less as lease expense over the lease term and those leases are not recorded on our Consolidated Balance Sheets. For additional information on our leases where the Company is the lessee, see Note 9- Leases. A significant portion of our device revenue is derived from patients who obtain our devices under month-to-month lease arrangements. Revenue related to devices on lease is recognized in accordance with ASC 842, Leases. Using the guidance in ASC 842, we concluded our transactions should be accounted for as operating leases based on the following criteria below: 1. The lease does not transfer ownership of the underlying asset to the lessee by the end of the lease term. 2. The lease does not grant the lessee an option to purchase the underlying asset that the lessee is reasonably certain to exercise. 3. The lease term is month to month, which does not meet the major part of the remaining economic life of the underlying asset. However, if the commencement date falls at or near the end of the economic life of the underlying asset, this criterion shall not be used for purposes of classifying the lease. 4. There is no residual value guaranteed and the present value of the sum of the lease payments does not equal or exceed substantially all of the fair value of the underlying asset 5. The underlying asset is expected to have alternative uses to the lessor at the end of the lease term. Lease commencement occurs upon delivery of the device to the patient. The Company retains title to the leased device and those devices are classified as property and equipment on the balance sheet. Since our leases are month-to-month and can be returned by the patient at any time, revenue is recognized monthly for the duration of the period in which the patient retains the device. Revenue Recognition, Accounts Receivable, Allowance for Billing Adjustments and Collectability Revenue is derived from sales and leases of our electrotherapy devices and sales of related supplies and complimentary products. The Company recognizes revenue when control of the product has been transferred to the patient, in the amount that reflects the consideration to which the Company expects to receive. In general, revenue from sales of our devices and supplies is recognized once the product is delivered to the patient, which is when control is deemed to have transferred to our patient. Sales of our devices and supplies are primarily made with, and shipped directly to the patient with a small amount of revenue generated from sales to distributors. In the healthcare industry there is often a third party involved that will pay on the patients’ behalf for purchased or leased devices and supplies. The terms of the separate arrangement impact certain aspects of the contracts, with patients covered by third party payers, such as contract type, performance obligations and transaction price, but for purposes of revenue recognition the contract with the customer refers to the arrangement between the Company and the patient. The Company does not have any material deferred revenue in the normal course of business as each performance obligation is met upon delivery of goods to the patient. There are no substantial costs incurred through support or warranty obligations. The following table provides a breakdown of net revenue related to devices accounted for as purchases subject to ASC 606 and leases subject to ASC 842 (in thousands): For the Year Ended December 31, 2019 2018 Device revenue Purchased $ 4,035 $ 1,950 Leased 6,678 4,872 Total Device revenue 10,713 6,822 Primarily all of the Company’s receivables are due from patients with commercial or government health plans and workers compensation claims with a small portion related to private pay individuals, attorney and auto claims. Revenues are estimated using the portfolio approach by third party payer type based upon historical rates of collection, aging of receivables, trends in historical reimbursement rates by third-party payer types, and current relationships and experience with the third-party payers, which includes estimated constraints for third-party payer refund requests, deductions and adjustments. Inherent in these estimates is the risk that they will have to be revised as additional information becomes available and constraints are released. Specifically, the complexity of third-party payer billing arrangements and the uncertainty of reimbursement amounts for certain products from third-party payers or unanticipated requirements to refund payments previously received may result in adjustments to amounts originally recorded. Due to continuing changes in the health care industry and third-party payer reimbursement, it is possible our forecasting model to estimate collections could change, which could have an impact on our results of operations and cash flows. Any differences between estimated and actual collectability are reflected in the period in which received. Historically these differences have been immaterial and the Company has not had to go back and reassess the adjustments of future periods for past billing adjustments. A change in the way estimates are determined can result from a number of factors, including changes in the reimbursement policies or practices of third-party payers, or changes in industry rates of reimbursement. The Company monitors the variability and uncertain timing over third-party payer types in our portfolios. If there is a change in our third-party payer mix over time, it could affect our net revenue and related receivables. We believe we have a sufficient history of collection experience to estimate the net collectible amounts by third-party payer type. However, changes to constraints for billing adjustments have historically fluctuated and may continue to fluctuate significantly from quarter to quarter and year to year. Stock-based Compensation The Company accounts for stock-based compensation through recognition of the cost of employee services received in exchange for an award of equity instruments, which is measured based on the grant date fair value of the award that is ultimately expected to vest during the period. The stock-based compensation expenses are recognized over the period during which an employee is required to provide service in exchange for the award (the requisite service period, which in the Company’s case is the same as the vesting period). For awards subject to the achievement of performance metrics, stock-based compensation expense is recognized when it becomes probable that the performance conditions will be achieved. Earnings Per Share We calculate basic earnings per share on the basis of the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share is calculated using the weighted-average number of shares of common stock outstanding for the period plus the effect of potential dilutive common shares during the period using the treasury stock method. Potential shares of common stock outstanding include unvested restricted stock awards, vested and unvested stock options and common stock purchase warrants. Advertising The Company expenses advertising costs as they are incurred. Advertising expense for each of the years ended December 31, 2019 and 2018 was approximately $0.3 million and $0.1 million, respectively. Research and Development Research and development costs are expensed when incurred. Research and development expense for the years ended December 31, 2019 and 2018 was approximately $0.6 million and $0.2 million, respectively. Research and development which includes salaries related to research and development and raw materials are included in general and administrative expenses on the consolidated statement of comprehensive income. Income Taxes We record deferred tax assets and liabilities for the estimated future tax effects of temporary differences between the tax bases of assets and liabilities and amounts reported in the accompanying consolidated balance sheets, as well as operating loss and tax credit carry-forwards. We measure deferred tax assets and liabilities using enacted tax rates expected to be applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. We reduce deferred tax assets by a valuation allowance if, based on available evidence, it is more likely than not that these benefits will not be realized. The Company is subject to the provisions of the Financial Accounting Standards Board (“FASB”) ASC 740‑10, Income Taxes, which requires that the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. Due to the complexities involved in accounting for the recently enacted Tax Act, the U.S. Securities and Exchange Commission’s Staff Accounting Bulletin (“SAB”) 118 allows a measurement period of up to one year after the enactment date of the Tax Act to finalize the recording of the related tax impacts. The company has finalized its analysis of tax impacts as of December 31, 2018 and has recorded no material adjustments. Recently Adopted Accounting Pronouncements In June 2018, the FASB issued ASU 2018‑07, Compensation-Stock Compensation (Topic 718), Improvements to Nonemployee Share-based Payments. This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The effective date for the standard is for interim periods in fiscal years beginning after December 15, 2018, with early adoption permitted. The new guidance is required to be applied retrospectively with the cumulative effect recognized at the date of initial application. The Company determined that adoption did not have a material impact on its consolidated financial statements. In February 2018, the FASB issued ASU 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (“ASU 2018-02”), which allows companies to reclassify stranded tax effects resulting from the 2017 Tax Cuts and Jobs Act (the Tax Act), from accumulated other comprehensive income to retained earnings. The new standard is effective for us beginning January 1, 2019, with early adoption permitted. The Company determined that the adoption did not have a material impact on its consolidated financial statements. The Company adopted ASU 2016-02, Leases (Topic 842), as of January 1, 2019, with an effective date of January 1, 2018, using the modified retrospective approach. The modified retrospective approach provides a method for recording existing leases at adoption and in comparative periods that approximates the results of a full retrospective approach. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standards, which among other things, allowed us to carry forward the historical lease classification. We also elected the hindsight practical expedient to determine the lease term for existing leases. Our election of the hindsight practical expedient resulted in the lengthening of the lease term related to one of our finance leases. Adoption of the new standard resulted in the recording of additional net lease assets and lease liabilities of approximately $3.6 million and $3.9 million, respectively, as of January 1, 2018. The difference between the additional lease assets and liabilities was primarily due to lease incentives with the remaining difference of $7,000 recorded as an adjustment to the opening balance of retained earnings. The standard did not have a material impact on our consolidated statement of operations and had no impact on our statement of cash flows. See Note 9, below, for further discussion regarding the Company’s operating and finance leases. Recently Issued Accounting Pronouncements In June 2016, FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) ("ASU 2016-13"), Measurement of Credit Losses on Financial Instruments. The standard significantly changes how entities will measure credit losses for most financial assets and certain other instruments that aren't measured at fair value through net income. The standard will replace today's "incurred loss" approach with an "expected loss" model for instruments measured at amortized cost. For available-for-sale debt securities, entities will be required to record allowances rather than reduce the carrying amount, as they do today under the other-than-temporary impairment model. It also simplifies the accounting model for purchased credit-impaired debt securities and loans. This ASU is effective for annual periods beginning after December 15, 2022, and interim periods therein for smaller reporting companies. Early adoption is permitted for annual periods beginning after December 15, 2018, and interim periods therein. The Corporation is currently evaluating the impact that the adoption of ASU 2016-13 will have on our financial condition, results of operations and cash flows. In December 2019, FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.” The amendments simplify the accounting for income taxes by removing certain exceptions to the general principals of Topic 740, “Income Taxes” and also improve consistent application by clarifying and amending existing guidance. The new standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption is permitted, with the amendments to be applied on a retrospective, modified retrospective or prospective basis, depending on the specific amendment. The Corporation is currently evaluating the impact of adoption this guidance. Management has evaluated other recently issued accounting pronouncements and does not believe that any of these pronouncements will have a material impact on the Company’s consolidated financial statements.

PROPERTY AND EQUIPMENT

PROPERTY AND EQUIPMENT	12 Months Ended
PROPERTY AND EQUIPMENT	Dec. 31, 2019
PROPERTY AND EQUIPMENT
PROPERTY AND EQUIPMENT	(3) PROPERTY AND EQUIPMENT The components of property and equipment are as follows (in thousands): December 31,2019 December 31,2018 Property and equipment Office furniture and equipment $ 1,178 $ 1,172 Assembly equipment 128 128 Vehicles 181 184 Leasehold improvements 500 480 Leased devices 934 317 $ 2,921 2,281 Less accumulated depreciation (2,063) (1,462) $ 858 $ 819 The Company monitors devices out on lease for potential loss and places an estimated reserve on the net book value based on historical loss rates. Total depreciation expense related to our purchased property and equipment was $0.3 million and $0.2 million for the years ended December 31, 2019 and 2018, respectively. Total depreciation expense related to devices out on lease was $0.5 million and $0.3 million for the years ended December 31, 2019 and 2018, respectively. Depreciation on leased units is reflected on the income statement as cost of revenue.

EARNINGS PER SHARE

EARNINGS PER SHARE	12 Months Ended
EARNINGS PER SHARE	Dec. 31, 2019
EARNINGS PER SHARE
EARNINGS PER SHARE	(4) EARNINGS PER SHARE The calculation of basic and diluted earnings per share for the years ended December 31, 2019 and 2018 are as follows (in thousands, except per share amounts): For the Years Ended December 31, 2019 2018 Basic earnings per share Net income available to common stockholders $ 9,492 $ 9,552 Basic weighted-average shares outstanding 32,439 32,503 Basic earnings per share $ 0.29 $ 0.29 Diluted earnings per share Net income available to common stockholders $ 9,492 $ 9,552 Weighted-average shares outstanding 32,439 32,503 Effect of dilutive securities - options and restricted stock 1,524 1,540 Diluted weighted-average shares outstanding 33,963 34,043 Diluted earnings per share $ 0.28 $ 0.28 For the years ended December 31, 2019 and 2018, 0.3 million and 0.4 million shares of common stock were excluded from the dilutive stock calculation because their effect would have been anti-dilutive.

STOCK-BASED COMPENSATION PLANS

STOCK-BASED COMPENSATION PLANS	12 Months Ended
STOCK-BASED COMPENSATION PLANS	Dec. 31, 2019
STOCK-BASED COMPENSATION PLANS
STOCK-BASED COMPENSATION PLANS	(5) STOCK-BASED COMPENSATION PLANS The Company’s 2017 Stock Incentive Plan (the “2017 Stock Plan”) is the Company’s equity compensation plan and provides for grants of stock-based awards to employees, directors and other individuals providing services to the Company. The 2017 Stock Plan authorizes the Company to award stock options and restricted stock. Awards issued under the 2017 Stock Plan are at the discretion of the Board of Directors. The 2017 Stock Plan mandates a maximum award term of 10 years and stipulates that stock options be granted with prices not less than fair market value on the date of grant. Stock option awards generally vest over four years. Restricted stock awards typically vest quarterly over three years for grants issued to members of our Board of Directors and quarterly or annually over four years for grants issued to employees. All awards granted under the 2017 Stock Plan are stock-settled with common stock issued upon the exercise of stock options or the vesting of restricted stock awards. At December 31, 2019, there were 1.2 million stock options and 0.1 million unvested restricted stock awards outstanding, and 3.7 million shares available for future grants under the 2017 Stock Plan. The Company previously reserved 3,000,000 shares of common stock for issuance under its 2005 Stock Option Plan (the “2005 Stock Plan”). The 2005 Stock Plan expired as of December 31, 2014. Vesting provisions of the expired plan were to be determined by the Board of Directors. All stock options under the 2005 Stock Plan expire no later than ten years from the date of grant. Options granted in 2015, 2016 and through May 2017 prior to the approval of the 2017 Stock Incentive Plan were approved and certified by the board of directors on September 6, 2017 under the existing 2005 stock option plan. At December 31, 2019, 0.7 million options remain outstanding under the 2005 stock option plan. The Company estimates the grant-date fair value of stock option awards using the Black-Scholes option pricing model and restricted stock awards at intrinsic value on the date of grant. The following assumptions were used in estimating the grant date fair value of stock options granted during the years ended December 31, 2019 and 2018: 2019 2018 Weighted average expected term 6.25 years 6.25 years Weighted average volatility 122 % 123 % Weighted average risk-free interest rate 2.30 % 3.00 % Dividend yield 0 % 0 % The weighted average expected term of stock options represents the period of time that the stock options granted are expected to be outstanding based on historical exercise trends. The weighted average expected volatility is based on the historical price volatility of the Company’s common stock. The weighted average risk-free interest rate represents the U.S. Treasury bill rate for the expected term of the related stock options. The dividend yield represents the Company’s anticipated cash dividend over the expected term of the stock options. Forfeitures are accounted for as they occur. The following table summarizes stock-based compensation expenses recorded in the condensed consolidated statements of operations (in thousands): For the Years Ended December 31, 2019 2018 Costs of revenue - devices and supplies $ 21 $ 33 Sales and marketing expense 205 127 General, and administrative 594 210 Total stock based compensation expense $ 820 $ 370 The excess tax benefit associated with our stock-based compensation plans for the years ended December 31, 2019 and 2018, was approximately $0.8 million and $0.3 million, respectively. A combined summary of stock option activity for the 2017 Stock Plan and the 2005 Stock Plan for the years ended December 31, 2019 and 2018 is presented below: Weighted Weighted Average Aggregate Average Remaining Intrinsic Number of Shares Strike Contractual Value (in thousands) Price Life (Years) (in thousands) Outstanding at December 31, 2017 2,142 $ 0.56 Granted 215 $ 2.99 Exercised (357) $ 0.44 Forfeited (115) $ 1.48 Outstanding at December 31, 2018 1,885 $ 0.80 6.32 $ 4,085 Outstanding at December 31, 2018 1,885 $ 0.80 Granted 653 $ 5.81 Exercised (503) $ 0.44 Expired (6) $ 1.00 Forfeited (174) $ 2.64 Outstanding at December 31, 2019 1,855 $ 2.48 6.42 $ 10,032 Exercisable at December 31, 2019 965 $ 0.60 $ 7,022 Outstanding Weighted average Number of Remaining Weighted Average Options Contractual Weighted Average Exercisable Number of Remaining Exercisable Exercisable Range (in thousands) Life (years) Strike Price Options (in thousands) Contractual Life (years) Strike Price $0 to $2.00 1,040 $ 0.42 889 3.80 $ 0.41 $2.01 to $4.00 367 $ 3.11 76 8.26 $ 2.78 $4.01 to $6.00 210 $ 5.35 — — $ — $6.01 to $8.00 $ — — $ — $8.01 to $10.00 38 $ 8.96 — — $ — 1,855 $ 2.48 965 4.15 $ 0.60 A summary of our unvested stock options as of December 31, 2019 and 2018 and related activity is presented below: Non-vested Shares Weighted Under Average Option Grant Date (in thousands) Fair Value Non-vested at December 31, 2017 658 $ 0.81 Granted 215 $ 2.65 Vested (256) $ 0.72 Forfeited (48) $ 1.98 Non-vested at December 31, 2018 569 $ 1.44 Non-vested at December 31, 2018 569 $ 1.44 Granted 653 $ 5.12 Vested (169) $ 1.24 Forfeited (163) $ 2.44 Non-vested at December 31, 2019 890 $ 4.03 A summary of restricted stock award activity under the 2017 Stock Plan for the years ended December 2019 and 2018 are presented below: Number of Shares Weighted Average (in thousands) Grant Date Fair Value Outstanding at December 31, 2017 15 $ 1.10 Granted 80 $ 3.56 Vested (19) $ 3.09 Outstanding at December 31, 2018 76 $ 3.19 Outstanding at December 31, 2018 76 $ 3.19 Granted 55 $ 8.10 Vested (29) $ 3.24 Outstanding at December 31, 2019 102 $ 5.81 As of December 31, 2019, there was approximately $3.5 million of total unrecognized compensation costs related to unvested stock options and restricted stock. These costs are expected to be recognized over a weighted average period of 2.9 years. The total intrinsic value of stock option exercises for the years ended December 31, 2019 and 2018 was $4.4 million and $1.1 million, respectively. The total fair value of restricted stock awards vested during the years ended December 31, 2019, and 2018 was $0.1 million and $0.2 million, respectively.

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	12 Months Ended
STOCKHOLDERS' EQUITY	Dec. 31, 2019
STOCKHOLDERS' EQUITY
STOCKHOLDERS' EQUITY	(6) STOCKHOLDERS’ EQUITY Common Stock Dividend Our Board of Directors declared a cash dividend of $0.07 per share on November 6, 2018. The dividend of $2.3 million was paid on January 18, 2019 to stockholders of record as of January 2, 2019. Any determination to declare a future quarterly dividend, as well as the amount of any cash dividend which may be declared, will be based on our financial position, earnings, earnings outlook and other relevant factors at that time. Treasury Stock From December 6, 2017 through March 6, 2018, we had the ability through our stock purchase program to re-purchase our common stock at prevailing market prices either in the open market or through privately negotiated transactions up to $2.0 million. On March 6, 2018, we reached the limit of $2.0 million and share re-purchases were ceased. From the inception of the plan through March 6, 2018, we purchased 495,091 shares of our common stock for $2.0 million or an average price of $4.04 per share. From May 14, 2018 through May 13, 2019, we had the ability through our stock repurchase program to re-purchase our common stock at prevailing market rates either in the open market or through privately negotiated transactions up to $2.0 million. From the inception of the plan through May 13, 2019, the Company purchased 576,129 shares of our common stock for $1.8 million or an average price of $3.20 per share. As of December 31, 2019 the Company had no outstanding stock repurchase programs. Warrants In October 2017, 150,000 common stock warrants were issued in exchange for professional services. In connection with the agreement entered into on March 28, 2016, with Triumph Bank, we issued a common stock warrant to purchase 50,000 shares of the Company’s common stock. A summary of stock warrant activity for the years ended December 31, 2019 and 2018 are presented below: Weighted Weighted Average Aggregate Number of Average Remaining Intrinsic Warrants Exercise Contractual Value (in thousands) Price Life (Years) (in thousands) Outstanding at December 31, 2017 200 $ 1.86 Granted — — Exercised (50) $ 0.20 Forfeited — $ — Outstanding and Exercisable at December 31, 2018 150 $ 2.42 5.77 $ 79 Outstanding at December 31, 2018 150 $ 2.42 5.77 $ 79 Granted — — Exercised (40) $ 2.00 Forfeited (1) (10) $ 2.00 Outstanding and Exercisable at December 31, 2019 100 $ 2.63 $ 525 (1) Warrants were exercised under a net exercise provision in the warrant agreement. As a result, approximately 10,000 warrants were forfeited in lieu of cash payment for shares.

INCOME TAXES

INCOME TAXES	12 Months Ended
INCOME TAXES	Dec. 31, 2019
INCOME TAXES
INCOME TAXES	(7) INCOME TAXES The pre-tax income from continuing operations on which the provision for income taxes was computed is as follows (in thousands): 2019 2018 United States $ 11,964 $ 10,237 Foreign (23) (21) Total 11,941 10,216 Income tax expense consists of the following for the years ended December 31, 2019 and 2018 (in thousands): 2019 2018 Current tax expense: Federal $ 1,865 $ 1,080 State 372 309 Total tax expense: 2,237 1,389 Deferred tax expense/(benefit): Federal 120 (462) State 92 (263) Total deferred tax expense/(benefit): $ 212 $ (725) Total $ 2,449 $ 664 A reconciliation of income tax computed at the U.S. statutory rate of 21% to the effective income tax rate is as follows: 2019 2018 Statutory rate 21 % 21 % State taxes 3 4 Permanent differences and other — 1 Change in valuation allowance (1) (16) Stock based compensation (4) (3) Other (true – up) 1 — Effective rate 20 % 7 % The tax effects of temporary differences that give rise to deferred tax assets (liabilities) at December 31, 2019 and 2018 are as follows (in thousands): 2019 2018 Deferred tax assets: Accrued expenses $ 34 $ 37 Lease liability 1,109 217 Accounts receivable 19 18 Inventory 232 117 Stock-based compensation 145 138 Tax Credits and NOL Carryforward 110 354 Other 1 150 Property and equipment — — Amortization 50 57 1,700 1,088 Less: Valuation allowance — (172) Deferred tax assets $ 1,700 $ 916 Deferred tax liabilities: Property and equipment $ (192) $ (176) Finance lease (45) — Right-of-use asset (946) — Prepaid expenses (4) (15) Deferred tax liabilities $ (1,187) $ (191) Net deferred tax assets $ 513 $ 725 For federal tax purposes, the Company completely utilized its remaining $2.7 million in NOL carryforwards as of December 31, 2018. As of December 31, 2019, the Company has NOL carryforwards in various states, which expire at various dates ranging from five to seven years. As of December 31, 2019 the Company had no recorded valuation allowance. As of December 31, 2018 the Company had a valuation allowance of $0.2 million. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers past history, the scheduled reversal of deferred tax liabilities, available taxes in carryback periods, projected future taxable income projections and tax planning strategies in making this assessment. During 2019, Management determined that no valuation is necessary and released the remaining valuation allowance. The accounting standard related to income taxes applies to all tax positions and defines the confidence level that a tax position must meet in order to be recognized in the financial statements. The accounting standard requires that the tax effects of a position be recognized only if it is "more-likely-than-not" to be sustained by the taxing authority as of the reporting date. If a tax position is not considered "more-likely-than-not" to be sustained, then no benefits of the position are to be recognized. Differences between financial and tax reporting which do not meet this threshold are required to be recorded as unrecognized tax benefits. This standard also provides guidance on the presentation of tax matters and the recognition of potential IRS interest and penalties. As of December 31, 2019 and 2018, the Company does not have an unrecognized tax liability. The Company does not classify penalty and interest expense related to income tax liabilities as an income tax expense. Penalties and interest are included within general and administrative expenses on the consolidated statements of operations. The Company files income tax returns in the U.S. and various state jurisdictions, and there are open statutes of limitations for taxing authorities to audit our tax returns from 2014 through the current period.

DEFERRED INSURANCE REIMBURSEMEN

DEFERRED INSURANCE REIMBURSEMENT	12 Months Ended
DEFERRED INSURANCE REIMBURSEMENT	Dec. 31, 2019
DEFERRED INSURANCE REIMBURSEMENT
DEFERRED INSURANCE REIMBURSEMENT	(8) DEFERRED INSURANCE REIMBURSEMENT During the first quarter of 2016, the Company collected $880,000 from a single insurance company for accounts receivable. The accounts receivable had been previously reduced to zero by the allowance for billing adjustments. Subsequent to March 31, 2016, the insurance company verbally communicated to the Company that this payment was made in error and requested it be refunded to the insurance company. The Company recorded this $880,000 insurance reimbursement as a deferred insurance liability. During the first quarter of 2019, the Company recognized $880,000 as other income and reversed the liability as management’s assessment was that any repayment obligation was deemed remote. The Company has included this amount in other income in order to ensure comparability of the Company’s operating income results for the years ended December 31, 2019 and 2018. Management’s legal determination that any refund obligation is remote was based on the facts and circumstances related to the dispute, which included reviewing the legal statutes within the jurisdictions the Company operates.

LEASES

LEASES	12 Months Ended
LEASES	Dec. 31, 2019
LEASES
LEASES	(9) LEASES The Company has three operating leases pertaining to its corporate headquarters located in Englewood, CO. Details of each lease are as follows: 1. The Company entered into a sublease agreement on October 20, 2017 with CSG Systems Inc. for approximately 41,715 square feet. The term of the sublease runs through June 30, 2023, with an option to extend for an additional two years through June 30, 2025. During the first year of the sublease, the rent per square foot is $7.50, increasing to $19.75 during the second year of the sublease and each year thereafter for the initial term increasing by an additional $1 per square foot. The Company has not yet determined whether it is reasonably certain to exercise its renewal option and has therefore only considered the initial term when determining the lease liability and lease asset. The Company is also obligated to pay its proportionate share of building operating expenses. The sub-landlord agreed to contribute approximately $0.2 million toward tenant improvements which is accounted for as a reduction of the operating lease asset and subsequently treated as a reduction of rent expense over the term of the lease. Upon lease commencement, the Company recorded an operating lease liability of $3.9 million and a corresponding right-of-use asset for $3.6 million. 2. The Company entered into an amendment to its sublease agreement, above, on March 11, 2019 for an additional 21,420 square feet of office space. The term of the sublease for the additional space began on June 1, 2019 and runs through June 30, 2023, with an option to extend the term for an additional two years through June 30, 2025. During the first seven months of the Amendment to the Sublease, the rent per square foot is $10.00, increasing to $20.75 from January 1, 2020 through October 31, 2020. For annual periods beginning November 1, 2020, the price per square foot increases by an additional $1 per square foot. The expansion work was completed, and the lease commenced, on June 1, 2019. Upon lease commencement, the Company recorded an operating lease liability and a corresponding right-of-use asset for $1.6 million each. 3. Subsequent to December 31, 2019, the Company entered into an amendment to its sublease agreement, above, on January 3, 2020 for an additional 22,546 square feet of office space. The term of the sublease will begin once certain expansion work is completed and will run through June 30, 2025. From the commencement date through October 31, 2020, the rent per square foot is $13.00, increasing to $21.75 per square foot from November 1, 2020 through October 31, 2021. The price per square foot increases by an additional $1 annually beginning November 1, 2021. The Company estimates that it will record a right-of-use asset and liability of $1.4 million each upon lease commencement. The Company has one finance lease for office equipment as follows: 4. The Company entered into an equipment lease on September 20, 2019 with Konica Minolta Premier Finance for a copier/printer and related software located at its corporate offices. The term of the equipment lease agreement is 5 years with the option to purchase the equipment at the end of the lease. The Company does not expect to exercise the option to purchase the equipment and, accordingly, has not considered the effect of the purchase in the evaluation of the lease asset and liability. Rent is to be paid monthly at a fixed rate for the term of the equipment lease agreement. Upon lease commencement, the Company recorded a finance lease liability and a corresponding right-of-use asset for $0.2 million each. The Company’s operating leases do not provide an implicit rate, and therefore the Company uses its incremental borrowing rate as the discount rate when measuring the lease liability. The incremental borrowing rate represents an estimate of the interest rate the Company would incur at lease commencement to borrow an amount equal to the lease payments on a collateralized basis over the term of a lease. The Company’s incremental borrowing rate was determined to be 4.8% for its operating lease liabilities. The Company’s equipment lease agreement has an implicit rate of 8.3%, which was used to measure its finance lease liability. The remaining lease term was 3.5 years for the Company’s operating leases and 4.8 years for its finance leases. The table below reconciles the undiscounted future minimum lease payments under the Company’s operating and finance leases to the total operating and capital lease liabilities recognized on the consolidated balance sheets as of December 31, 2019 (in thousands): Operating lease liabilities Finance lease liabilities 2020 $ 1,344 $ 57 2021 1,408 45 2022 1,473 45 2023 763 45 2024 — 34 Total undiscounted future minimum lease payments 4,988 226 Less: Difference between undiscounted lease payments and discounted lease liabilities: (495) (36) Total lease liabilities $ 4,493 $ 190 Operating and finance lease costs were $1.2 million and $0.9 million for years ended December 31, 2019 and 2018, which were included in the consolidated statement of operations under the following headings (in thousands): For the years ended December 31, Operating Lease expense 2019 2018 Costs of revenue - devices and supplies $ 121 $ 142 Sales and marketing expense 170 114 General and administrative 859 670 Total operating lease expense $ 1,150 $ 926 Finance Lease expense Amortization of right-of-use asset: Costs of revenue - devices and supplies $ 2 $ — Sales and marketing expense 4 — General and administrative 13 10 Total amortization of right-of-use asset 19 10 Interest expense and other 5 2 Total finance lease expense $ 24 $ 12

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
COMMITMENTS AND CONTINGENCIES	Dec. 31, 2019
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES	(10) COMMITMENTS AND CONTINGENCIES See Note 9 for details regarding commitments under the Company’s long-term leases. From time to time, the Company may become party to litigation and other claims in the ordinary course of business. To the extent that such claims and litigation arise, management would provide for them if losses are determined to be both probable and estimable. The Company is currently not a party to any material pending legal proceedings.

CONCENTRATIONS

CONCENTRATIONS	12 Months Ended
CONCENTRATIONS	Dec. 31, 2019
CONCENTRATIONS
CONCENTRATIONS	(11) CONCENTRATIONS The Company is exposed to concentration of credit risk related primarily to its cash balances. The Company maintains its cash at major financial institutions. The Company has not experienced any realized losses in such accounts and believes it is not exposed to any significant credit risk related to its cash. The Company had one major vendor from which is sourced approximately 49% of supplies for its electrotherapy products for the years ended December 31, 2019 and 2018. Management believes that its relationships with its suppliers are good. If the relationships were to be replaced, there may be a short-term disruption for a period of time in which products may not be available and additional expenses may be incurred as the Company locates additional or replacement suppliers. The Company had receivables from two third-party payers at December 31, 2019, which made up approximately 39% of the accounts receivable balance. The Company had receivables from a third-party payer at December 31, 2018, which made up approximately 23% of the accounts receivable balance.

RETIREMENT PLAN

RETIREMENT PLAN	12 Months Ended
RETIREMENT PLAN	Dec. 31, 2019
RETIREMENT PLAN
RETIREMENT PLAN	(12) RETIREMENT PLAN In 2012, the Company established a defined contribution retirement plan for its employees under section 401(k) of the Internal Revenue Code (the “401(k) Plan”) that is available to all employees 18 years of age or older with three months of service. All employee contributions are fully vested immediately and employer contributions vest over a period of four years. The Company has a discretionary employee match program and currently matches 35% of first 6% of an employee’s contributions. During each of 2019 and 2018, The Company recorded an expense of $0.1 million under the aforementioned plan, related to the Company match.

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
RELATED PARTY TRANSACTIONS	Dec. 31, 2019
RELATED PARTY TRANSACTIONS
RELATED PARTY TRANSACTIONS	(13) RELATED PARTY TRANSACTIONS In 2015, the Company entered into a three-year employment agreement totaling $0.1 million with Mr. Joachim Sandgaard, Mr. Sandgaard’s son. This arrangement concluded at the end of 2018. No further payments were made in 2019.

QUARTERLY FINANCIAL INFORMATION

QUARTERLY FINANCIAL INFORMATION (UNAUDITED)	12 Months Ended
QUARTERLY FINANCIAL INFORMATION (UNAUDITED)	Dec. 31, 2019
QUARTERLY FINANCIAL INFORMATION (UNAUDITED)
QUARTERLY FINANCIAL INFORMATION (UNAUDITED)	(14) QUARTERLY FINANCIAL INFORMATION (UNAUDITED) Quarterly financial information is as follows (in thousands, except per share data): 2018 First Quarter Second Quarter Third Quarter Fourth Quarter Total Revenue $ 6,876 $ 7,573 $ 8,131 $ 9,337 Less: cost of revenue and operating expenses 4,921 4,858 5,312 6,457 Income from operations 1,955 2,715 2,819 2,880 Income before income taxes 1,840 2,678 2,818 2,880 Net income $ 1,921 $ 2,418 $ 2,591 $ 2,622 Net income per common share: Basic income per share - net income $ 0.06 $ 0.07 $ 0.08 $ 0.08 Diluted income per share - net income $ 0.06 $ 0.07 $ 0.07 $ 0.08 2019 First Quarter Second Quarter Third Quarter Fourth Quarter Total Revenue $ 9,196 $ 10,297 $ 11,817 $ 14,162 Less: cost of revenue and operating expenses 6,940 7,713 9,322 10,431 Income from operations 2,256 2,584 2,495 3,731 Income before income taxes 3,136 2,584 2,496 3,725 Net income $ 2,350 $ 2,162 $ 2,033 $ 2,947 Net income per common share: Basic income per share - net income $ 0.07 $ 0.07 $ 0.06 $ 0.09 Diluted income per share - net income $ 0.07 $ 0.06 $ 0.06 $ 0.09

SUBSEQUENT EVENT

SUBSEQUENT EVENT	12 Months Ended
SUBSEQUENT EVENT	Dec. 31, 2019
SUBSEQUENT EVENT
SUBSEQUENT EVENT	(15) SUBSEQUENT EVENTS See Note 9 – Leases above for a discussion regarding the lease agreement entered into in January 2020. On February 25, 2020 the Company announced the FDA granted 510(k) clearance for sale in the U.S. for the CM-1500 Blood Volume Monitor.

SIGNIFICANT ACCOUNTING POLICI_2

SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
SIGNIFICANT ACCOUNTING POLICIES (Policies)	Dec. 31, 2019
SIGNIFICANT ACCOUNTING POLICIES
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of Zynex, Inc. and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Non-controlling Interest	Non-controlling Interest Non-controlling interest in the equity of a subsidiary is accounted for and reported as a decrease in shareholders’ equity. Non-controlling interest represents the 20% ownership in the Company’s majority-owned inactive subsidiary, ZBC.
Reclassifications	Reclassifications During 2019, the Company began reporting costs related to its selling and marketing activities separate from its general and administrative costs. As a result, reclassifications between selling and marketing costs and general and administrative costs have been made to the results of operations for the year ended December 31, 2018 to conform to the consolidated 2019 financial statement presentation. These reclassifications had no effect on net earnings, retained earnings or cash flows as previously reported.
Use of Estimates	Use of Estimates Preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. The most significant management estimates used in the preparation of the accompanying consolidated financial statements are associated with the allowance for billing adjustments and uncollectible accounts receivable, inventory reserves, the life of its leased devices, stock-based compensation, and valuation of long-lived assets and realizability of deferred tax assets.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company’s financial instruments include cash, accounts receivable, accounts payable, and accrued liabilities, for which current carrying amounts approximate fair value due to their short-term nature.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. Short-term investments include investments with maturities greater than three months, but not exceeding 12 months, or highly liquid investments with maturities greater than 12 months that the Company intends to liquidate during the next 12 months for working capital needs.
Inventory	Inventory Inventories are stated at the lower of cost and net realizable value. Cost is computed using standard costs, which approximates actual costs on an average cost basis. Following are the components of inventory as of December 31, 2019 and 2018 (in thousands): December 31, 2019 December 31, 2018 Raw Materials $ 953 $ 454 Work-in-process 200 55 Finished Goods 1,640 576 $ 2,793 1,085 Less: reserve (415) (248) $ 2,378 $ 837 The Company monitors inventory for turnover and obsolescence and records losses for excess and obsolete inventory, as appropriate. The Company provides reserves for estimated excess and obsolete inventories equal to the difference between the costs of inventories on hand and the estimated market value based upon assumptions about future demand. If future demand is less favorable than currently projected by management, additional inventory write-downs may be required.
Property and Equipment	Property and Equipment Property and equipment is recorded at cost. Repairs and maintenance expenditures are charged to expense as incurred. We compute depreciation expense on a straight-line basis over the estimated useful lives of the assets as follows: Classification Estimated Useful Life Office furniture and equipment 5 to 7 years Assembly equipment 7 years Vehicles 5 years Leasehold improvements Term of lease Leased devices 9 months
Leases	Leases The Company determines if an arrangement is a lease at inception or modification of a contract. The Company recognizes finance and operating lease right-of-use assets and liabilities at the lease commencement date based on the estimated present value of the lease payments over the lease term. For our finance leases, the Company uses the implicit rate to determine the present value of future lease payments. For our operating leases that do not provide an implicit rate, the Company uses incremental borrowing rates to determine the present value of future lease payments. The Company includes options to extend or terminate a lease in the lease term when it is reasonably certain to exercise such options. The Company recognizes leases with an initial term of 12 months or less as lease expense over the lease term and those leases are not recorded on our Consolidated Balance Sheets. For additional information on our leases where the Company is the lessee, see Note 9- Leases. A significant portion of our device revenue is derived from patients who obtain our devices under month-to-month lease arrangements. Revenue related to devices on lease is recognized in accordance with ASC 842, Leases. Using the guidance in ASC 842, we concluded our transactions should be accounted for as operating leases based on the following criteria below: 1. The lease does not transfer ownership of the underlying asset to the lessee by the end of the lease term. 2. The lease does not grant the lessee an option to purchase the underlying asset that the lessee is reasonably certain to exercise. 3. The lease term is month to month, which does not meet the major part of the remaining economic life of the underlying asset. However, if the commencement date falls at or near the end of the economic life of the underlying asset, this criterion shall not be used for purposes of classifying the lease. 4. There is no residual value guaranteed and the present value of the sum of the lease payments does not equal or exceed substantially all of the fair value of the underlying asset 5. The underlying asset is expected to have alternative uses to the lessor at the end of the lease term. Lease commencement occurs upon delivery of the device to the patient. The Company retains title to the leased device and those devices are classified as property and equipment on the balance sheet. Since our leases are month-to-month and can be returned by the patient at any time, revenue is recognized monthly for the duration of the period in which the patient retains the device.
Revenue Recognition, Accounts Receivable, Allowance for Billing Adjustments and Collectability	Revenue Recognition, Accounts Receivable, Allowance for Billing Adjustments and Collectability Revenue is derived from sales and leases of our electrotherapy devices and sales of related supplies and complimentary products. The Company recognizes revenue when control of the product has been transferred to the patient, in the amount that reflects the consideration to which the Company expects to receive. In general, revenue from sales of our devices and supplies is recognized once the product is delivered to the patient, which is when control is deemed to have transferred to our patient. Sales of our devices and supplies are primarily made with, and shipped directly to the patient with a small amount of revenue generated from sales to distributors. In the healthcare industry there is often a third party involved that will pay on the patients’ behalf for purchased or leased devices and supplies. The terms of the separate arrangement impact certain aspects of the contracts, with patients covered by third party payers, such as contract type, performance obligations and transaction price, but for purposes of revenue recognition the contract with the customer refers to the arrangement between the Company and the patient. The Company does not have any material deferred revenue in the normal course of business as each performance obligation is met upon delivery of goods to the patient. There are no substantial costs incurred through support or warranty obligations. The following table provides a breakdown of net revenue related to devices accounted for as purchases subject to ASC 606 and leases subject to ASC 842 (in thousands): For the Year Ended December 31, 2019 2018 Device revenue Purchased $ 4,035 $ 1,950 Leased 6,678 4,872 Total Device revenue 10,713 6,822 Primarily all of the Company’s receivables are due from patients with commercial or government health plans and workers compensation claims with a small portion related to private pay individuals, attorney and auto claims. Revenues are estimated using the portfolio approach by third party payer type based upon historical rates of collection, aging of receivables, trends in historical reimbursement rates by third-party payer types, and current relationships and experience with the third-party payers, which includes estimated constraints for third-party payer refund requests, deductions and adjustments. Inherent in these estimates is the risk that they will have to be revised as additional information becomes available and constraints are released. Specifically, the complexity of third-party payer billing arrangements and the uncertainty of reimbursement amounts for certain products from third-party payers or unanticipated requirements to refund payments previously received may result in adjustments to amounts originally recorded. Due to continuing changes in the health care industry and third-party payer reimbursement, it is possible our forecasting model to estimate collections could change, which could have an impact on our results of operations and cash flows. Any differences between estimated and actual collectability are reflected in the period in which received. Historically these differences have been immaterial and the Company has not had to go back and reassess the adjustments of future periods for past billing adjustments. A change in the way estimates are determined can result from a number of factors, including changes in the reimbursement policies or practices of third-party payers, or changes in industry rates of reimbursement. The Company monitors the variability and uncertain timing over third-party payer types in our portfolios. If there is a change in our third-party payer mix over time, it could affect our net revenue and related receivables. We believe we have a sufficient history of collection experience to estimate the net collectible amounts by third-party payer type. However, changes to constraints for billing adjustments have historically fluctuated and may continue to fluctuate significantly from quarter to quarter and year to year.
Stock-based Compensation	Stock-based Compensation The Company accounts for stock-based compensation through recognition of the cost of employee services received in exchange for an award of equity instruments, which is measured based on the grant date fair value of the award that is ultimately expected to vest during the period. The stock-based compensation expenses are recognized over the period during which an employee is required to provide service in exchange for the award (the requisite service period, which in the Company’s case is the same as the vesting period). For awards subject to the achievement of performance metrics, stock-based compensation expense is recognized when it becomes probable that the performance conditions will be achieved. E
Earnings Per Share	Earnings Per Share We calculate basic earnings per share on the basis of the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share is calculated using the weighted-average number of shares of common stock outstanding for the period plus the effect of potential dilutive common shares during the period using the treasury stock method. Potential shares of common stock outstanding include unvested restricted stock awards, vested and unvested stock options and common stock purchase warrants.
Advertising	Advertising The Company expenses advertising costs as they are incurred. Advertising expense for each of the years ended December 31, 2019 and 2018 was approximately $0.3 million and $0.1 million, respectively.
Research and Development	Research and Development Research and development costs are expensed when incurred. Research and development expense for the years ended December 31, 2019 and 2018 was approximately $0.6 million and $0.2 million, respectively. Research and development which includes salaries related to research and development and raw materials are included in general and administrative expenses on the consolidated statement of comprehensive income.
Income Taxes	Income Taxes We record deferred tax assets and liabilities for the estimated future tax effects of temporary differences between the tax bases of assets and liabilities and amounts reported in the accompanying consolidated balance sheets, as well as operating loss and tax credit carry-forwards. We measure deferred tax assets and liabilities using enacted tax rates expected to be applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. We reduce deferred tax assets by a valuation allowance if, based on available evidence, it is more likely than not that these benefits will not be realized. The Company is subject to the provisions of the Financial Accounting Standards Board (“FASB”) ASC 740‑10, Income Taxes, which requires that the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. Due to the complexities involved in accounting for the recently enacted Tax Act, the U.S. Securities and Exchange Commission’s Staff Accounting Bulletin (“SAB”) 118 allows a measurement period of up to one year after the enactment date of the Tax Act to finalize the recording of the related tax impacts. The company has finalized its analysis of tax impacts as of December 31, 2018 and has recorded no material adjustments.
Recently Adopted and Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements In June 2018, the FASB issued ASU 2018‑07, Compensation-Stock Compensation (Topic 718), Improvements to Nonemployee Share-based Payments. This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The effective date for the standard is for interim periods in fiscal years beginning after December 15, 2018, with early adoption permitted. The new guidance is required to be applied retrospectively with the cumulative effect recognized at the date of initial application. The Company determined that adoption did not have a material impact on its consolidated financial statements. In February 2018, the FASB issued ASU 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (“ASU 2018-02”), which allows companies to reclassify stranded tax effects resulting from the 2017 Tax Cuts and Jobs Act (the Tax Act), from accumulated other comprehensive income to retained earnings. The new standard is effective for us beginning January 1, 2019, with early adoption permitted. The Company determined that the adoption did not have a material impact on its consolidated financial statements. The Company adopted ASU 2016-02, Leases (Topic 842), as of January 1, 2019, with an effective date of January 1, 2018, using the modified retrospective approach. The modified retrospective approach provides a method for recording existing leases at adoption and in comparative periods that approximates the results of a full retrospective approach. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standards, which among other things, allowed us to carry forward the historical lease classification. We also elected the hindsight practical expedient to determine the lease term for existing leases. Our election of the hindsight practical expedient resulted in the lengthening of the lease term related to one of our finance leases. Adoption of the new standard resulted in the recording of additional net lease assets and lease liabilities of approximately $3.6 million and $3.9 million, respectively, as of January 1, 2018. The difference between the additional lease assets and liabilities was primarily due to lease incentives with the remaining difference of $7,000 recorded as an adjustment to the opening balance of retained earnings. The standard did not have a material impact on our consolidated statement of operations and had no impact on our statement of cash flows. See Note 9, below, for further discussion regarding the Company’s operating and finance leases. Recently Issued Accounting Pronouncements In June 2016, FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) ("ASU 2016-13"), Measurement of Credit Losses on Financial Instruments. The standard significantly changes how entities will measure credit losses for most financial assets and certain other instruments that aren't measured at fair value through net income. The standard will replace today's "incurred loss" approach with an "expected loss" model for instruments measured at amortized cost. For available-for-sale debt securities, entities will be required to record allowances rather than reduce the carrying amount, as they do today under the other-than-temporary impairment model. It also simplifies the accounting model for purchased credit-impaired debt securities and loans. This ASU is effective for annual periods beginning after December 15, 2022, and interim periods therein for smaller reporting companies. Early adoption is permitted for annual periods beginning after December 15, 2018, and interim periods therein. The Corporation is currently evaluating the impact that the adoption of ASU 2016-13 will have on our financial condition, results of operations and cash flows. In December 2019, FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.” The amendments simplify the accounting for income taxes by removing certain exceptions to the general principals of Topic 740, “Income Taxes” and also improve consistent application by clarifying and amending existing guidance. The new standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption is permitted, with the amendments to be applied on a retrospective, modified retrospective or prospective basis, depending on the specific amendment. The Corporation is currently evaluating the impact of adoption this guidance. Management has evaluated other recently issued accounting pronouncements and does not believe that any of these pronouncements will have a material impact on the Company’s consolidated financial statements.

SIGNIFICANT ACCOUNTING POLICI_3

SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
SIGNIFICANT ACCOUNTING POLICIES (Tables)	Dec. 31, 2019
SIGNIFICANT ACCOUNTING POLICIES
Schedule of components of inventory	Following are the components of inventory as of December 31, 2019 and 2018 (in thousands): December 31, 2019 December 31, 2018 Raw Materials $ 953 $ 454 Work-in-process 200 55 Finished Goods 1,640 576 $ 2,793 1,085 Less: reserve (415) (248) $ 2,378 $ 837
Schedule of estimated useful lives of the assets	We compute depreciation expense on a straight-line basis over the estimated useful lives of the assets as follows: Classification Estimated Useful Life Office furniture and equipment 5 to 7 years Assembly equipment 7 years Vehicles 5 years Leasehold improvements Term of lease Leased devices 9 months
Schedule of breakdown of net revenue related to devices accounted for as purchases subject to ASC 606 and leases subject to ASC 842	The following table provides a breakdown of net revenue related to devices accounted for as purchases subject to ASC 606 and leases subject to ASC 842 (in thousands): For the Year Ended December 31, 2019 2018 Device revenue Purchased $ 4,035 $ 1,950 Leased 6,678 4,872 Total Device revenue 10,713 6,822

PROPERTY AND EQUIPMENT (Tables)

PROPERTY AND EQUIPMENT (Tables)	12 Months Ended
PROPERTY AND EQUIPMENT (Tables)	Dec. 31, 2019
PROPERTY AND EQUIPMENT
Schedule of components of property and equipment	The components of property and equipment are as follows (in thousands): December 31,2019 December 31,2018 Property and equipment Office furniture and equipment $ 1,178 $ 1,172 Assembly equipment 128 128 Vehicles 181 184 Leasehold improvements 500 480 Leased devices 934 317 $ 2,921 2,281 Less accumulated depreciation (2,063) (1,462) $ 858 $ 819

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	12 Months Ended
EARNINGS PER SHARE (Tables)	Dec. 31, 2019
EARNINGS PER SHARE
Schedule of Calculation of Basic and Diluted earnings per share	The calculation of basic and diluted earnings per share for the years ended December 31, 2019 and 2018 are as follows (in thousands, except per share amounts): For the Years Ended December 31, 2019 2018 Basic earnings per share Net income available to common stockholders $ 9,492 $ 9,552 Basic weighted-average shares outstanding 32,439 32,503 Basic earnings per share $ 0.29 $ 0.29 Diluted earnings per share Net income available to common stockholders $ 9,492 $ 9,552 Weighted-average shares outstanding 32,439 32,503 Effect of dilutive securities - options and restricted stock 1,524 1,540 Diluted weighted-average shares outstanding 33,963 34,043 Diluted earnings per share $ 0.28 $ 0.28

STOCK-BASED COMPENSATION PLANS

STOCK-BASED COMPENSATION PLANS (Tables)	12 Months Ended
STOCK-BASED COMPENSATION PLANS (Tables)	Dec. 31, 2019
STOCK-BASED COMPENSATION PLANS
Fair Value of Stock Options Grants	The following assumptions were used in estimating the grant date fair value of stock options granted during the years ended December 31, 2019 and 2018: 2019 2018 Weighted average expected term 6.25 years 6.25 years Weighted average volatility 122 % 123 % Weighted average risk-free interest rate 2.30 % 3.00 % Dividend yield 0 % 0 %
Schedule of share based compensation expenses recorded in the consolidated statement of income	The following table summarizes stock-based compensation expenses recorded in the condensed consolidated statements of operations (in thousands): For the Years Ended December 31, 2019 2018 Costs of revenue - devices and supplies $ 21 $ 33 Sales and marketing expense 205 127 General, and administrative 594 210 Total stock based compensation expense $ 820 $ 370
Summary of Stock Option Activity Under the Option Plan	Weighted Weighted Average Aggregate Average Remaining Intrinsic Number of Shares Strike Contractual Value (in thousands) Price Life (Years) (in thousands) Outstanding at December 31, 2017 2,142 $ 0.56 Granted 215 $ 2.99 Exercised (357) $ 0.44 Forfeited (115) $ 1.48 Outstanding at December 31, 2018 1,885 $ 0.80 6.32 $ 4,085 Outstanding at December 31, 2018 1,885 $ 0.80 Granted 653 $ 5.81 Exercised (503) $ 0.44 Expired (6) $ 1.00 Forfeited (174) $ 2.64 Outstanding at December 31, 2019 1,855 $ 2.48 6.42 $ 10,032 Exercisable at December 31, 2019 965 $ 0.60 $ 7,022
Summary of Stock Options Outstanding Under The Plans	Outstanding Weighted average Number of Remaining Weighted Average Options Contractual Weighted Average Exercisable Number of Remaining Exercisable Exercisable Range (in thousands) Life (years) Strike Price Options (in thousands) Contractual Life (years) Strike Price $0 to $2.00 1,040 $ 0.42 889 3.80 $ 0.41 $2.01 to $4.00 367 $ 3.11 76 8.26 $ 2.78 $4.01 to $6.00 210 $ 5.35 — — $ — $6.01 to $8.00 $ — — $ — $8.01 to $10.00 38 $ 8.96 — — $ — 1,855 $ 2.48 965 4.15 $ 0.60
Restricted Stock Award Activity Under all Equity Compensation Plans	A summary of our unvested stock options as of December 31, 2019 and 2018 and related activity is presented below: Non-vested Shares Weighted Under Average Option Grant Date (in thousands) Fair Value Non-vested at December 31, 2017 658 $ 0.81 Granted 215 $ 2.65 Vested (256) $ 0.72 Forfeited (48) $ 1.98 Non-vested at December 31, 2018 569 $ 1.44 Non-vested at December 31, 2018 569 $ 1.44 Granted 653 $ 5.12 Vested (169) $ 1.24 Forfeited (163) $ 2.44 Non-vested at December 31, 2019 890 $ 4.03 A summary of restricted stock award activity under the 2017 Stock Plan for the years ended December 2019 and 2018 are presented below: Number of Shares Weighted Average (in thousands) Grant Date Fair Value Outstanding at December 31, 2017 15 $ 1.10 Granted 80 $ 3.56 Vested (19) $ 3.09 Outstanding at December 31, 2018 76 $ 3.19 Outstanding at December 31, 2018 76 $ 3.19 Granted 55 $ 8.10 Vested (29) $ 3.24 Outstanding at December 31, 2019 102 $ 5.81

STOCKHOLDERS' EQUITY (Tables)

STOCKHOLDERS' EQUITY (Tables)	12 Months Ended
STOCKHOLDERS' EQUITY (Tables)	Dec. 31, 2019
Fair Value of Stock Options Grants	The following assumptions were used in estimating the grant date fair value of stock options granted during the years ended December 31, 2019 and 2018: 2019 2018 Weighted average expected term 6.25 years 6.25 years Weighted average volatility 122 % 123 % Weighted average risk-free interest rate 2.30 % 3.00 % Dividend yield 0 % 0 %
Warrant [Member]
Schedule of stock warrant activity	A summary of stock warrant activity for the years ended December 31, 2019 and 2018 are presented below: Weighted Weighted Average Aggregate Number of Average Remaining Intrinsic Warrants Exercise Contractual Value (in thousands) Price Life (Years) (in thousands) Outstanding at December 31, 2017 200 $ 1.86 Granted — — Exercised (50) $ 0.20 Forfeited — $ — Outstanding and Exercisable at December 31, 2018 150 $ 2.42 5.77 $ 79 Outstanding at December 31, 2018 150 $ 2.42 5.77 $ 79 Granted — — Exercised (40) $ 2.00 Forfeited (1) (10) $ 2.00 Outstanding and Exercisable at December 31, 2019 100 $ 2.63 $ 525 (1) Warrants were exercised under a net exercise provision in the warrant agreement. As a result, approximately 10,000 warrants were forfeited in lieu of cash payment for shares.

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
INCOME TAXES (Tables)	Dec. 31, 2019
INCOME TAXES
Schedule of pre-tax income from continuing operations on which the provision for income taxes	The pre-tax income from continuing operations on which the provision for income taxes was computed is as follows (in thousands): 2019 2018 United States $ 11,964 $ 10,237 Foreign (23) (21) Total 11,941 10,216
Schedule of income tax expense	Income tax expense consists of the following for the years ended December 31, 2019 and 2018 (in thousands): 2019 2018 Current tax expense: Federal $ 1,865 $ 1,080 State 372 309 Total tax expense: 2,237 1,389 Deferred tax expense/(benefit): Federal 120 (462) State 92 (263) Total deferred tax expense/(benefit): $ 212 $ (725) Total $ 2,449 $ 664
Schedule of reconciliation of income tax	A reconciliation of income tax computed at the U.S. statutory rate of 21% to the effective income tax rate is as follows: 2019 2018 Statutory rate 21 % 21 % State taxes 3 4 Permanent differences and other — 1 Change in valuation allowance (1) (16) Stock based compensation (4) (3) Other (true – up) 1 — Effective rate 20 % 7 %
Schedule of tax effects of temporary differences that give rise to deferred tax assets (liabilities)	The tax effects of temporary differences that give rise to deferred tax assets (liabilities) at December 31, 2019 and 2018 are as follows (in thousands): 2019 2018 Deferred tax assets: Accrued expenses $ 34 $ 37 Lease liability 1,109 217 Accounts receivable 19 18 Inventory 232 117 Stock-based compensation 145 138 Tax Credits and NOL Carryforward 110 354 Other 1 150 Property and equipment — — Amortization 50 57 1,700 1,088 Less: Valuation allowance — (172) Deferred tax assets $ 1,700 $ 916 Deferred tax liabilities: Property and equipment $ (192) $ (176) Finance lease (45) — Right-of-use asset (946) — Prepaid expenses (4) (15) Deferred tax liabilities $ (1,187) $ (191) Net deferred tax assets $ 513 $ 725

LEASES (Tables)

LEASES (Tables)	12 Months Ended
LEASES (Tables)	Dec. 31, 2019
LEASES
Schedule of future minimum lease payments under the Company's operating leases	The table below reconciles the undiscounted future minimum lease payments under the Company’s operating and finance leases to the total operating and capital lease liabilities recognized on the consolidated balance sheets as of December 31, 2019 (in thousands): Operating lease liabilities Finance lease liabilities 2020 $ 1,344 $ 57 2021 1,408 45 2022 1,473 45 2023 763 45 2024 — 34 Total undiscounted future minimum lease payments 4,988 226 Less: Difference between undiscounted lease payments and discounted lease liabilities: (495) (36) Total lease liabilities $ 4,493 $ 190
Schedule of future minimum lease payments under the Company's financing leases	The table below reconciles the undiscounted future minimum lease payments under the Company’s operating and finance leases to the total operating and capital lease liabilities recognized on the consolidated balance sheets as of December 31, 2019 (in thousands): Operating lease liabilities Finance lease liabilities 2020 $ 1,344 $ 57 2021 1,408 45 2022 1,473 45 2023 763 45 2024 — 34 Total undiscounted future minimum lease payments 4,988 226 Less: Difference between undiscounted lease payments and discounted lease liabilities: (495) (36) Total lease liabilities $ 4,493 $ 190
Schedule of lease cost	For the years ended December 31, Operating Lease expense 2019 2018 Costs of revenue - devices and supplies $ 121 $ 142 Sales and marketing expense 170 114 General and administrative 859 670 Total operating lease expense $ 1,150 $ 926 Finance Lease expense Amortization of right-of-use asset: Costs of revenue - devices and supplies $ 2 $ — Sales and marketing expense 4 — General and administrative 13 10 Total amortization of right-of-use asset 19 10 Interest expense and other 5 2 Total finance lease expense $ 24 $ 12

QUARTERLY FINANCIAL INFORMATI_2

QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Tables)	12 Months Ended
QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Tables)	Dec. 31, 2019
QUARTERLY FINANCIAL INFORMATION (UNAUDITED)
Schedule of quarterly financial information	Quarterly financial information is as follows (in thousands, except per share data): 2018 First Quarter Second Quarter Third Quarter Fourth Quarter Total Revenue $ 6,876 $ 7,573 $ 8,131 $ 9,337 Less: cost of revenue and operating expenses 4,921 4,858 5,312 6,457 Income from operations 1,955 2,715 2,819 2,880 Income before income taxes 1,840 2,678 2,818 2,880 Net income $ 1,921 $ 2,418 $ 2,591 $ 2,622 Net income per common share: Basic income per share - net income $ 0.06 $ 0.07 $ 0.08 $ 0.08 Diluted income per share - net income $ 0.06 $ 0.07 $ 0.07 $ 0.08 2019 First Quarter Second Quarter Third Quarter Fourth Quarter Total Revenue $ 9,196 $ 10,297 $ 11,817 $ 14,162 Less: cost of revenue and operating expenses 6,940 7,713 9,322 10,431 Income from operations 2,256 2,584 2,495 3,731 Income before income taxes 3,136 2,584 2,496 3,725 Net income $ 2,350 $ 2,162 $ 2,033 $ 2,947 Net income per common share: Basic income per share - net income $ 0.07 $ 0.07 $ 0.06 $ 0.09 Diluted income per share - net income $ 0.07 $ 0.06 $ 0.06 $ 0.09

ORGANIZATION, NATURE OF BUSIN_2

ORGANIZATION, NATURE OF BUSINESS AND MANAGEMENT'S PLANS - Additional Information (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Zynex Billing And Consultancy, LLC [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	80.00%
North America [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Percentage Of Revenues	99.99%	99.99%

SIGNIFICANT ACCOUNTING POLICI_4

SIGNIFICANT ACCOUNTING POLICIES - Non-controlling Interest (Details)	Dec. 31, 2019
Zynex Billing And Consultancy, LLC [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Non-controlling interest (as a percentage)	20.00%

SIGNIFICANT ACCOUNTING POLICI_5

SIGNIFICANT ACCOUNTING POLICIES - Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Components of inventory
Raw Materials	$ 953	$ 454
Work-in-process	200	55
Finished Goods	1,640	576
Total	2,793	1,085
Less: reserve	(415)	(248)
Inventory, net	$ 2,378	$ 837

SIGNIFICANT ACCOUNTING POLICI_6

SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2019
Office furniture and equipment \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	5 years
Office furniture and equipment \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	7 years
Assembly equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	7 years
Vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	5 years
Leased devices
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	9 months

SIGNIFICANT ACCOUNTING POLICI_7

SIGNIFICANT ACCOUNTING POLICIES - Leases (Details)	12 Months Ended
SIGNIFICANT ACCOUNTING POLICIES - Leases (Details)	Dec. 31, 2019
SIGNIFICANT ACCOUNTING POLICIES
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Lessee, Operating Lease, Existence of Option to Terminate [true false]	true

SIGNIFICANT ACCOUNTING POLICI_8

SIGNIFICANT ACCOUNTING POLICIES - Breakdown of net revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Device revenue
Total Device revenue	$ 14,162	$ 11,817	$ 10,297	$ 9,196	$ 9,337	$ 8,131	$ 7,573	$ 6,876	$ 45,472	$ 31,917
Devices [Member]
Device revenue
Purchased									4,035	1,950
Leased									6,678	4,872
Total Device revenue									$ 10,713	$ 6,822

SIGNIFICANT ACCOUNTING POLICI_9

SIGNIFICANT ACCOUNTING POLICIES - Additional information (Details) - USD ($) $ in Thousands	Jan. 01, 2018	Dec. 31, 2019	Dec. 31, 2018
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Advertising Expense		$ 300	$ 100
Research and Development Expense		$ 600	200
Cumulative Effect on Retained Earnings, Net of Tax			$ (7)
ASU 2016-02
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Lease, Practical Expedients, Package [true false]	true
Lease, Practical Expedient, Use of Hindsight [true false]	true
Net lease assets	$ 3,600
Net lease liabilities	$ 3,900

PROPERTY AND EQUIPMENT (Details

PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment, Gross	$ 2,921	$ 2,281
Less accumulated depreciation	(2,063)	(1,462)
Property and Equipment, Net	858	819
Office furniture and equipment
Property, Plant and Equipment, Gross	1,178	1,172
Assembly equipment
Property, Plant and Equipment, Gross	128	128
Vehicles
Property, Plant and Equipment, Gross	181	184
Leasehold improvements
Property, Plant and Equipment, Gross	500	480
Leased devices
Property, Plant and Equipment, Gross	$ 934	$ 317

PROPERTY AND EQUIPMENT - Additi

PROPERTY AND EQUIPMENT - Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Depreciation	$ 778	$ 448
Property and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation	300	200
Leased Devices [Member]
Property, Plant and Equipment [Line Items]
Depreciation	$ 500	$ 300

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Basic earnings per share
Net income available to common stockholders	$ 2,947	$ 2,033	$ 2,162	$ 2,350	$ 2,622	$ 2,591	$ 2,418	$ 1,921	$ 9,492	$ 9,552
Basic weighted-average shares outstanding									32,439	32,503
Basic earnings per share									$ 0.29	$ 0.29
Diluted earnings per share
Net income available to common stockholders	$ 2,947	$ 2,033	$ 2,162	$ 2,350	$ 2,622	$ 2,591	$ 2,418	$ 1,921	$ 9,492	$ 9,552
Weighted-average shares outstanding									32,439	32,503
Effect of dilutive securities - options and restricted stock									1,524	1,540
Diluted weighted-average shares outstanding									33,963	34,043
Diluted earnings per share									$ 0.28	$ 0.28

EARNINGS PER SHARE - Additional

EARNINGS PER SHARE - Additional information (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.3	0.4

STOCK-BASED COMPENSATION PLAN_2

STOCK-BASED COMPENSATION PLANS - Stock options granted (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair value of stock option grants
Weighted average expected term	6 years 3 months	6 years 3 months
Weighted average risk-free interest rate	2.30%	3.00%
Weighted average volatility	122.00%	123.00%
Dividend yield	0.00%	0.00%

STOCK-BASED COMPENSATION PLAN_3

STOCK-BASED COMPENSATION PLANS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allocated Share-based Compensation Expense	$ 820	$ 370
Costs of revenue - devices and supplies
Allocated Share-based Compensation Expense	21	33
Sales and marketing expense
Allocated Share-based Compensation Expense	205	127
General, and administrative
Allocated Share-based Compensation Expense	$ 594	$ 210

STOCK-BASED COMPENSATION PLAN_4

STOCK-BASED COMPENSATION PLANS - Summary of stock option activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Summary of stock option activity under the option Plan
Weighted Average Remaining Contractual Life, Exercisable (Years)	4 years 1 month 24 days
Employee Stock Option [Member]
Summary of stock option activity under the option Plan
Outstanding at beginning	1,885	2,142
Number of Shares, Granted	653	215
Number of Shares, Expired	(6)
Number of Shares, Forfeited	(174)	(115)
Number of Warrants, Exercised	(503)	(357)
Outstanding at ending	1,855	1,885
Number of Shares, Exercisable	965
Weighted Average Exercise Price, Outstanding Beginning	$ 0.80	$ 0.56
Weighted Average Exercise Price, Granted	5.81	2.99
Weighted Average Exercise Price, Expired	1
Weighted Average Exercise Price, Exercised	0.44	0.44
Weighted Average Exercise Price, Forfeited	2.64	1.48
Weighted Average Exercise Price, Outstanding Ending	2.48	$ 0.80
Weighted Average Exercise Price, Exercisable	$ 0.60
Weighted Average Remaining Contractual Life, Outstanding	6 years 5 months 1 day	6 years 3 months 26 days
Weighted Average Remaining Contractual Life, Exercisable (Years)	4 years 1 month 24 days
Aggregate Intrinsic Value, Outstanding	$ 10,032	$ 4,085
Aggregate Intrinsic Value, Exercisable	$ 7,022

STOCK-BASED COMPENSATION PLAN_5

STOCK-BASED COMPENSATION PLANS - Stock Plan (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Outstanding Number of Shares \| shares \| shares	1,855
WA Remaining Contractual Life (years)	6 years 5 months 1 day
WA Outstanding Strike Price	$ 2.48
Exercisable Number of Shares \| shares \| shares	965
Remaining Exercisable Contractual Life (years)	4 years 1 month 24 days
WA Exercisable Strike Price	$ 0.60
Exercise Price Range One [Member]
Exercise Price Minimum	0
Exercise Price Maximum	$ 2
Outstanding Number of Shares \| shares \| shares	1,040
WA Remaining Contractual Life (years)	4 years 3 months 29 days
WA Outstanding Strike Price	$ 0.42
Exercisable Number of Shares \| shares \| shares	889
Remaining Exercisable Contractual Life (years)	3 years 9 months 18 days
WA Exercisable Strike Price	$ 0.41
Exercise Price Range Two [Member]
Exercise Price Minimum	2.01
Exercise Price Maximum	$ 4
Outstanding Number of Shares \| shares \| shares	367
WA Remaining Contractual Life (years)	8 years 8 months 5 days
WA Outstanding Strike Price	$ 3.11
Exercisable Number of Shares \| shares \| shares	76
Remaining Exercisable Contractual Life (years)	8 years 3 months 4 days
WA Exercisable Strike Price	$ 2.78
Exercise Price Range Three [Member]
Exercise Price Minimum	4.01
Exercise Price Maximum	$ 6
Outstanding Number of Shares \| shares \| shares	210
WA Remaining Contractual Life (years)	9 years 2 months 5 days
WA Outstanding Strike Price	$ 5.35
Remaining Exercisable Contractual Life (years)	0 years
Exercise Price Range Four [Member]
Exercise Price Minimum	$ 6.01
Exercise Price Maximum	$ 8
Outstanding Number of Shares \| shares \| shares	200
WA Remaining Contractual Life (years)	9 years 6 months 22 days
WA Outstanding Strike Price	$ 7.87
Remaining Exercisable Contractual Life (years)	0 years
Exercise Price Range Five [Member]
Exercise Price Minimum	$ 8.01
Exercise Price Maximum	$ 10
Outstanding Number of Shares \| shares \| shares	38
WA Remaining Contractual Life (years)	9 years 10 months 10 days
WA Outstanding Strike Price	$ 8.96
Remaining Exercisable Contractual Life (years)	0 years

STOCK-BASED COMPENSATION PLAN_6

STOCK-BASED COMPENSATION PLANS - Summary of our unvested stock options (Details) - Non vested Share Awards [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Non-vested Shares Under Option, Beginning Balance	569	658
Non-vested Shares Under Option, Granted	653	215
Non-vested Shares Under Option, Vested	(169)	(256)
Non-vested Shares Under Option, Forfeited	(163)	(48)
Non-vested Shares Under Option, Ending Balance	890	569
Weighted Average Grant Date Fair Value, Beginning Balance	$ 1.44	$ 0.81
Weighted Average Grant Date Fair Value, Granted	5.12	2.65
Weighted Average Grant Date Fair Value, Vested	1.24	0.72
Weighted Average Grant Date Fair Value, Forfeited	2.44	1.98
Weighted Average Grant Date Fair Value, Ending Balance	$ 4.03	$ 1.44

STOCK-BASED COMPENSATION PLAN_7

STOCK-BASED COMPENSATION PLANS - Summary of restricted stock award activity (Details) - Restricted Stock [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at Beginning	76	15
Granted	55	80
Vested	(29)	(19)
Outstanding At Ending	102	76
Weighted Average Grant Date Fair Value, Beginning Balance	$ 3.19	$ 1.10
Weighted Average Grant Date Fair Value, Granted	8.10	3.56
Weighted Average Grant Date Fair Value, Vested	3.24	3.09
Weighted Average Grant Date Fair Value, Ending Balance	$ 5.81	$ 3.19

STOCK-BASED COMPENSATION PLAN_8

STOCK-BASED COMPENSATION PLANS - Additional information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Proceeds from Stock Options Exercised	$ 0.8	$ 0.3
Unrecognized compensation expense related to stock options	$ 3.5
Weighted-average period of unrecognized compensation expense related to stock options	2 years 10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 4.4	1.1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 0.1	$ 0.2
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	102,000	76,000	15,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	55,000	80,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 8.10	$ 3.56
Stock Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock options remain reserved for issuance	3,700,000
Stock Incentive Plan 2017 [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Stock Incentive Plan 2017 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	700,000
Stock Incentive Plan 2017 [Member] \| Restricted Stock [Member] \| Share-based Payment Arrangement, Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Stock Incentive Plan 2017 [Member] \| Restricted Stock [Member] \| Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
2005 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	700,000

STOCKHOLDERS' EQUITY - Warrants

STOCKHOLDERS' EQUITY - Warrants (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Weighted Average Remaining Contractual Life, Exercisable (Years)	4 years 1 month 24 days
Warrant [Member]
Outstanding at beginning	150	200
Number of Warrants, Exercised	(40)	(50)
Number of Warrants, Forfeited	(10)
Outstanding at ending	100	150
Number of Warrants, Exercisable	100	150
Weighted Average Exercise Price, Outstanding Beginning	$ 2.42	$ 1.86
Weighted Average Exercise Price, Exercised	2	0.20
Weighted Average Exercise Price, Forfeited	2
Weighted Average Exercise Price, Outstanding Ending	2.63	2.42
Weighted Average Exercise Price, Exercisable	$ 2.63	$ 2.42
Weighted Average Remaining Contractual Life (Years)	4 years 9 months 7 days	5 years 9 months 7 days
Weighted Average Remaining Contractual Life, Exercisable (Years)	4 years 9 months 7 days	5 years 9 months 7 days
Aggregate Intrinsic Value	$ 525	$ 79
Aggregate Intrinsic Value, Exercisable	$ 525	$ 79

STOCKHOLDERS' EQUITY - Addition

STOCKHOLDERS' EQUITY - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
	Oct. 31, 2017	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2019	May 13, 2019	Dec. 31, 2018	May 14, 2018	Mar. 06, 2018	Mar. 28, 2016
Subsidiary, Sale of Stock [Line Items]
Dividends Payable, Amount Per Share			$ 0.07			$ 0.07
Dividends Payable, Current			$ 2,270	$ 8		$ 2,270
Stock Repurchase Program, Authorized Amount								$ 2,000
Stock Repurchased During Period, Shares			576,129
Treasury Stock Acquired, Average Cost Per Share		$ 4.04			$ 3.20
Stock Repurchase Program Additional Authorized Amount							$ 2,000
Stock Repurchased During Period, Value		$ 2,000		$ 171	$ 1,800	$ 3,432
Common Stock Warrants Issued For Professional Services	150,000
Common Stock
Subsidiary, Sale of Stock [Line Items]
Stock Repurchased During Period, Shares		495,091		52,000		932,383
Warrant exercises (in shares)				40,366
Triumph Bank [Member]
Subsidiary, Sale of Stock [Line Items]
Number of warrants exercised									50,000

INCOME TAXES - Pre-tax income f

INCOME TAXES - Pre-tax income from continuing operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
INCOME TAXES
United States	$ 11,964	$ 10,237
Foreign	(23)	(21)
Total	$ 11,941	$ 10,216

INCOME TAXES - Income tax expen

INCOME TAXES - Income tax expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Current tax expense:
Federal	$ 1,865	$ 1,080
State	372	309
Total tax expense:	2,237	1,389
Deferred tax expense/(benefit):
Federal	120	(462)
State	92	(263)
Total deferred tax expense/(benefit):	212	(725)
Total	$ 2,449	$ 664

INCOME TAXES - Reconciliation o

INCOME TAXES - Reconciliation of income tax (Details)	12 Months Ended
INCOME TAXES - Reconciliation of income tax (Details)	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory rate	21.00%	21.00%
State taxes	3.00%	4.00%
Permanent differences and other		1.00%
Change in valuation allowance	(1.00%)	(16.00%)
Stock based compensation	(4.00%)	(3.00%)
Other (true - up)	1.00%
Effective rate	20.00%	7.00%

INCOME TAXES - Tax effects of t

INCOME TAXES - Tax effects of temporary differences (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Accrued expenses	$ 34	$ 37
Lease liability	1,109	217
Accounts receivable	19	18
Inventory	232	117
Stock-based compensation	145	138
Tax Credits and NOL Carryforward	110	354
Other	1	150
Amortization	50	57
Total deferred tax assets	1,700	1,088
Less: Valuation allowance		(172)
Deferred tax assets	1,700	916
Deferred tax liabilities:
Property and equipment	(192)	(176)
Finance lease	(45)
Right-of-use asset	(946)
Prepaid expenses	(4)	(15)
Deferred tax liabilities	(1,187)	(191)
Net deferred tax assets	$ 513	$ 725

INCOME TAXES - Additional infor

INCOME TAXES - Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation, Percent	20.00%	7.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Income Tax Expense (Benefit)	$ 2,449	$ 664
Deferred Tax Assets, Valuation Allowance		172
Net income Loss Carry forward For Income Tax Purpose		$ 2,700
Maximum [Member]
Income Taxes [Line Items]
Net Operating Loss Carry Forwards Expiration Period	7 years
Minimum [Member]
Income Taxes [Line Items]
Net Operating Loss Carry Forwards Expiration Period	5 years

DEFERRED INSURANCE REIMBURSEM_2

DEFERRED INSURANCE REIMBURSEMENT (Details) - USD ($)	12 Months Ended
DEFERRED INSURANCE REIMBURSEMENT (Details) - USD ($)	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2016
DEFERRED INSURANCE REIMBURSEMENT
Liability for Claims and Claims Adjustment Expense, Total	$ 0		$ 880,000	$ 880,000
Deferred Insurance Liability		$ 880,000
Deferred insurance reimbursement	$ 880,000

LEASES (Details)

LEASES (Details) - USD ($) $ in Thousands	Jan. 03, 2020	Dec. 31, 2019	Sep. 20, 2019	Jun. 01, 2019	Oct. 20, 2017
Operating lease liabilities
2020		$ 1,344
2021		1,408
2022		1,473
2023		763
Total undiscounted future minimum lease payments		4,988
Less: Difference between undiscounted lease payments and discounted operating lease liabilities:		(495)
Operating Lease, Liability, Total	$ 1,400	4,493		$ 1,600	$ 3,900
Finance lease liabilities
2020		57
2021		45
2022		45
2023		45
2024		34
Total undiscounted future minimum lease payments		226
Less: Difference between undiscounted lease payments and discounted lease liabilities:		(36)
Total lease liabilities		$ 190	$ 200

LEASES - Lease cost (Details)

LEASES - Lease cost (Details) - USD ($) $ in Thousands	12 Months Ended
LEASES - Lease cost (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Leases
Total operating lease expense	$ 1,150	$ 926
Total amortization of right-of-use asset	19	10
Interest expense and other	5	2
Total finance lease expense	24	12
Costs of revenue - devices and supplies
Leases
Total operating lease expense	121	142
Total amortization of right-of-use asset	2
Sales and marketing expense
Leases
Total operating lease expense	170	114
Total amortization of right-of-use asset	4
General, and administrative
Leases
Total operating lease expense	859	670
Total amortization of right-of-use asset	$ 13	$ 10

LEASES - Additional information

LEASES - Additional information (Details) $ in Thousands	Nov. 01, 2021$ / ft²	Nov. 01, 2020$ / ft²	Sep. 30, 2019$ / ft²	Oct. 31, 2020$ / ft²	Oct. 31, 2020$ / ft²	Dec. 31, 2019USD ($)	Oct. 20, 2019$ / ft²	Oct. 19, 2019$ / ft²	Dec. 31, 2018USD ($)	Oct. 19, 2018$ / ft²	Oct. 31, 2021$ / ft²	Jan. 03, 2020USD ($)a	Sep. 20, 2019USD ($)	Jun. 01, 2019USD ($)	Mar. 11, 2019a	Oct. 20, 2017USD ($)a
LEASES
Land Subject to Ground Leases \| a												22,546			21,420	41,715
Option to extend (in years)															2 years	2 years
Rent per square foot \| $ / ft²			10	13	20.75			19.75		7.50	21.75
Additional rent per square foot \| $ / ft²	1	1					1
Tenant Improvements																$ 200
Operating lease liabilities						$ 4,493						$ 1,400		$ 1,600		3,900
Operating lease asset						3,831			$ 3,050			$ 1,400		$ 1,600		$ 3,600
Finance Lease, Right-of-Use Asset						180			19				$ 200
Finance Lease, Liability						190							$ 200
Lessee, Operating Lease, Term of Contract													5 years
Operating and finance lease cost						$ 1,200			$ 900
Lessee, Operating Lease, Discount Rate						4.80%
Lessee, Finance Lease, Discount Rate						8.30%
Operating Lease, Weighted Average Remaining Lease Term						3 years 6 months
Finance Lease, Weighted Average Remaining Lease Term						4 years 9 months 18 days

CONCENTRATIONS (Details)

CONCENTRATIONS (Details) - item	12 Months Ended
CONCENTRATIONS (Details) - item	Dec. 31, 2019	Dec. 31, 2018
Supplier Concentration Risk [Member] \| Cost of Goods, Total [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	49.00%	49.00%
Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	39.00%	23.00%
Number of third-party payers	2	1

RETIREMENT PLAN - Additional in

RETIREMENT PLAN - Additional information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2012
RETIREMENT PLAN
Defined Contribution Plan Eligibility Age	18 years
Defined Contribution Plan Period Of Employment For Eligibility	3 months
Defined Contribution Plan, Cost	$ 0.1	$ 0.1
Defined Contribution Plan Description of Employer Matching Contribution			The Company has a discretionary employee match program and currently matches 35% of first 6% of an employee's contributions.
Defined Contribution Plan, Employer Matching Contribution, Percent of Match			35.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay			6.00%

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - Employment Arrangement - Immediate Family Members of Management or Principal Owner $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)
RELATED PARTY TRANSACTIONS
Lump sum payment	$ 0.1
Agreement term	3 years

QUARTERLY FINANCIAL INFORMATI_3

QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
QUARTERLY FINANCIAL INFORMATION (UNAUDITED)
Total Revenue	$ 14,162	$ 11,817	$ 10,297	$ 9,196	$ 9,337	$ 8,131	$ 7,573	$ 6,876	$ 45,472	$ 31,917
Less: cost of revenue and operating expenses	10,431	9,322	7,713	6,940	6,457	5,312	4,858	4,921	34,406	21,547
Income from operations	3,731	2,495	2,584	2,256	2,880	2,819	2,715	1,955	11,066	10,370
Income before income taxes	3,725	2,496	2,584	3,136	2,880	2,818	2,678	1,840
Net income	$ 2,947	$ 2,033	$ 2,162	$ 2,350	$ 2,622	$ 2,591	$ 2,418	$ 1,921	$ 9,492	$ 9,552
Net income per common share:
Basic income per share - net income	$ 0.09	$ 0.06	$ 0.07	$ 0.07	$ 0.08	$ 0.08	$ 0.07	$ 0.06
Diluted income per share - net income	$ 0.09	$ 0.06	$ 0.06	$ 0.07	$ 0.08	$ 0.07	$ 0.07	$ 0.06