Forescout (FSCT) 10-Q11 May 202020 Q1 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2020	May 01, 2020
Cover [Abstract]
Document Type	10-Q
Document Fiscal Period Focus	Q1
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Amendment Flag	false
Document Fiscal Year Focus	2020
Current Fiscal Year End Date	--12-31
Entity File Number	001-38253
Entity Registrant Name	FORESCOUT TECHNOLOGIES, INC
Entity Central Index Key	0001145057
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	51-0406800
Entity Address, Address Line One	190 West Tasman Drive
Entity Address, City or Town	San Jose
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95134
City Area Code	408
Local Phone Number	213-3191
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	FSCT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		49,264,795

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 83,795	$ 69,030
Marketable securities	16,126	29,181
Accounts receivable	39,650	84,168
Inventory	377	372
Deferred commissions - current	12,854	12,843
Prepaid expenses and other current assets	12,867	17,024
Total current assets	165,669	212,618
Deferred commissions - non-current	21,294	23,036
Property and equipment, net	22,618	23,835
Operating lease right-of-use assets	28,326	29,626
Restricted cash - non-current	1,530	1,555
Intangible assets, net	18,353	19,367
Goodwill	98,018	98,018
Other assets	7,460	8,172
Total assets	363,268	416,227
Current liabilities:
Accounts payable	6,377	10,692
Accrued compensation	26,881	34,007
Accrued expenses	15,397	16,279
Deferred revenue - current	111,402	112,232
Notes payable - current	6,402	8,248
Revolving credit facility	16,000	0
Operating lease liabilities - current	5,704	5,840
Total current liabilities	188,163	187,298
Deferred revenue - non-current	68,438	75,366
Operating lease liabilities - non-current	30,333	32,125
Other liabilities	23,705	23,893
Total liabilities	310,639	318,682
Stockholders' equity:
Common stock	49	48
Additional paid-in capital	744,299	727,922
Accumulated other comprehensive loss	(688)	(633)
Accumulated deficit	(691,031)	(629,792)
Total stockholders’ equity	52,629	97,545
Total liabilities and stockholders' equity	$ 363,268	$ 416,227

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	49,040,000	48,064,000
Common stock, shares outstanding (in shares)	49,040,000	48,064,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue:
Revenue	$ 57,153	$ 75,568
Cost of revenue:
Cost of revenue	19,597	19,000
Total gross profit	37,556	56,568
Operating expenses:
Research and development	23,246	18,497
Sales and marketing	47,288	55,923
General and administrative	24,481	16,213
Restructuring	2,512	0
Total operating expenses	97,527	90,633
Loss from operations	(59,971)	(34,065)
Interest expense	(235)	(93)
Other (expense) income, net	(601)	617
Loss before income taxes	(60,807)	(33,541)
Income tax provision	432	711
Net loss	$ (61,239)	$ (34,252)
Net loss per share, basic and diluted (in dollars per share)	$ (1.26)	$ (0.78)
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)	48,593	44,196
License
Revenue:
Revenue	$ 14,799	$ 37,680
Cost of revenue:
Cost of revenue	5,419	7,607
Subscription
Revenue:
Revenue	37,526	33,799
Cost of revenue:
Cost of revenue	7,013	5,207
Professional services
Revenue:
Revenue	4,828	4,089
Cost of revenue:
Cost of revenue	$ 7,165	$ 6,186

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (61,239)	$ (34,252)
Other comprehensive (loss) income, net of tax:
Change in fair value adjustment on marketable securities	(55)	75
Foreign currency translation adjustments	0	(2,054)
Comprehensive loss	$ (61,294)	$ (36,231)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2018		43,403,000
Stockholders' equity, beginning balance at Dec. 31, 2018	$ 127,721	$ 43	$ 639,237	$ (302)	$ (511,257)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive loss, net of tax	(1,979)			(1,979)
Stock-based compensation	13,828		13,828
Issuance of common stock in connection with employee equity incentive plans (in shares)		1,706,000
Issuance of common stock in connection with employee equity incentive plans	9,409	$ 2	9,407
Vesting of early exercised stock options (in shares)		24,000
Vesting of early exercised stock options	202	$ 0	202
Net loss	(34,252)				(34,252)
Stockholders' equity, ending balance (in shares) at Mar. 31, 2019		45,133,000
Stockholders' equity, ending balance at Mar. 31, 2019	$ 114,929	$ 45	662,674	(2,281)	(545,509)
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2019	48,064,000	48,064,000
Stockholders' equity, beginning balance at Dec. 31, 2019	$ 97,545	$ 48	727,922	(633)	(629,792)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive loss, net of tax	(55)			(55)
Stock-based compensation	$ 13,478		13,478
Issuance of common stock in connection with employee equity incentive plans (in shares)	450,000	976,000
Issuance of common stock in connection with employee equity incentive plans	$ 2,900	$ 1	2,899
Net loss	$ (61,239)				(61,239)
Stockholders' equity, ending balance (in shares) at Mar. 31, 2020	49,040,000	49,040,000
Stockholders' equity, ending balance at Mar. 31, 2020	$ 52,629	$ 49	$ 744,299	$ (688)	$ (691,031)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net loss	$ (61,239)	$ (34,252)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities
Stock-based compensation	13,858	13,828
Depreciation and amortization	3,056	2,845
Other	358	(15)
Changes in operating assets and liabilities
Accounts receivable	44,518	22,227
Inventory	(196)	253
Deferred commissions	1,731	1,520
Prepaid expenses and other current assets	4,168	(203)
Other assets	328	385
Accounts payable	(4,274)	(2,705)
Accrued compensation	(7,126)	(4,512)
Accrued expenses	(1,715)	549
Deferred revenue	(7,758)	6,559
Other liabilities	(172)	(40)
Net cash (used in) provided by operating activities	(14,463)	6,439
Cash flows from investing activities:
Purchases of property and equipment	(823)	(1,589)
Purchases of marketable securities	0	(37,651)
Proceeds from maturities of marketable securities	13,000	29,123
Net cash provided by (used in) investing activities	12,177	(10,117)
Cash flows from financing activities:
Proceeds from revolving credit facility	16,000	0
Repayments of notes payable	(1,875)	(1,875)
Proceeds from sales of shares through employee equity incentive plans	5,207	12,173
Payment related to shares withheld for taxes on vesting of restricted stock units	(2,319)	(2,764)
Others	13	0
Net cash provided by financing activities	17,026	7,534
Effect of exchange rate changes on cash and cash equivalents	0	(70)
Net change in cash, cash equivalents, and restricted cash for period	14,740	3,786
Cash, cash equivalents, and restricted cash at beginning of period	71,591	69,012
Cash, cash equivalents, and restricted cash at end of period	86,331	72,798
Reconciliation of cash, cash equivalents, and restricted cash within the condensed consolidated balance sheets to the amounts shown in the statements of cash flows above:
Total cash, cash equivalents, and restricted cash	$ 86,331	$ 72,798

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Summary of Significant Accounting Policies	Description of Business and Summary of Significant Accounting Policies Company and Background Forescout Technologies, Inc. (the “Company”) was incorporated in the State of Delaware and commenced operations in April 2000. The Company designs, develops, and markets device visibility, control, and orchestration software that helps organizations gain complete situational awareness of all devices in their interconnected environment and orchestrate actions to mitigate both their cyber and operational risk. The Company offers its solution across two product groups: (i) products for visibility and control capabilities, and (ii) products for orchestration capabilities. The Company’s products for visibility and control capabilities consist of eyeSight, eyeSegment, eyeControl, and SilentDefense; eyeSight, eyeSegment, and eyeControl provide for visibility and control capabilities across the extended enterprise, from campus to data center to hybrid cloud to operational technology (“OT”) devices, while SilentDefense provides for visibility and control capabilities deeper within the OT portion of the network. The Company’s products for orchestration capabilities are comprised of its portfolio of eyeExtend family of products. The Company offers its solution across two product types: (i) software products and (ii) hardware products. The Company’s software products include eyeSight, eyeSegment, eyeControl, eyeExtend, SilentDefense, and SilentDefense Command Center (“Software Products”). The Company’s hardware products include hardware that is sold separately for use with the Company’s Software Products and appliances that are embedded with the Company’s software (“Hardware Products”). The Company sells its Software Products, Hardware Products, support and maintenance contracts, and professional services to end-customers through distributors and resellers, who are supported by the Company’s sales and marketing organization, and to a lesser extent directly to end-customers. Proposed Merger On February 6, 2020, the Company entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Ferrari Group Holdings, L.P., a Delaware limited partnership (“Parent”), and Ferrari Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Parent (“Merger Sub”). Parent and Merger Sub are affiliates of Advent. The Merger Agreement provides that, subject to the terms and conditions set forth in the Merger Agreement, Merger Sub will merge with and into the Company (the “Merger”), with the Company surviving the Merger and becoming a wholly owned subsidiary of Parent (the “Surviving Corporation”). Under the Merger Agreement, at the effective time of the Merger, each issued and outstanding share of the Company’s common stock (except for certain shares specified in the Merger Agreement) will be canceled and automatically converted into the right to receive cash in an amount equal to $33.00 , without interest. Consummation of the Merger is subject to the satisfaction or waiver of customary closing conditions, including (1) approval of the Merger Agreement by the Company’s stockholders; (2) the absence of any law or order restraining, enjoining or otherwise prohibiting the Merger; and (3) the expiration or termination of the waiting period under the United States Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and clearance under the antitrust laws of certain non-United States jurisdictions. On February 24, 2020, the U.S. Federal Trade Commission granted early termination of the waiting period under the HSR Act. On April 23, 2020, our stockholders approved the Merger Agreement. The Merger is expected to close in the second fiscal quarter of 2020. Upon consummation of the Merger, the Company’s common stock will no longer be listed on any public market. COVID-19 Due to the COVID-19 pandemic, there has been uncertainty and disruption in the global economy and financial markets, which has decreased, and may further decrease, demand for a broad variety of goods and services, while also disrupting sales channels and marketing activities for an unknown period of time until the pandemic is contained. At this point, the extent to which COVID-19 may impact our financial condition or results of operations is uncertain. Basis of Presentation The accompanying condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) using accounting policies that are consistent with those used in the preparation of the Company’s audited consolidated financial statements for the year ended December 31, 2019 . Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) have been condensed or omitted as permitted by the SEC's rules and regulations. The Company’s condensed consolidated financial statements include the results of Forescout Technologies, Inc. and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated financial statements are unaudited and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, necessary for the fair presentation of the Company’s quarterly results. The condensed consolidated balance sheet as of December 31, 2019 was derived from the audited consolidated financial statements at that date but does not include all the disclosures required by GAAP for the annual financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019 . The preparation of interim condensed consolidated financial statements in conformity with GAAP requires management to make use of estimates and assumptions that affect the reported amounts in the condensed consolidated financial statements and accompanying notes, including but not limited to the potential impacts arising from the recent COVID-19 and public and private policies and initiatives aimed at reducing its transmission. These estimates form the basis of judgments made about carrying values of assets and liabilities, which are not readily apparent from other sources. The areas where management has made estimates requiring judgment include, but are not limited to, the best estimate of standalone selling prices for license and related support, the period over which deferred sales commissions are amortized to expense, accruals, stock-based compensation, provision for income taxes including related reserves, identified intangibles and goodwill, purchase price allocation of an acquired business, and incremental borrowing rate for operating leases. As the extent and duration of the impact from COVID-19 continue to evolve and additional information becomes available, the Company’s estimates and assumptions may change materially in future periods. Actual results could differ materially from those estimates. Summary of Significant Accounting Policies Restructuring cost The Company records restructuring activities including costs for one-time termination benefits in accordance with ASC Topic 420 (“ASC 420”), Exit or Disposal Cost Obligations. A liability is recognized when management has committed to a restructuring plan and has communicated those actions to employees. Restructuring cost for employee workforce reductions are recorded upon employee notification for employees whose required continuing service period is 60 days or less and ratably over the employee’s continuing service period for employees whose required continuing service period is greater than 60 days . Employee termination benefits covered by existing benefit arrangements are recorded in accordance with ASC Topic 712, Non-retirement Post-employment Benefits. These costs are recognized as restructuring charges in the condensed consolidated statement of operations when management has committed to a restructuring plan and the severance costs are probable and estimable. Refer to Note 5 for further details. Credit losses Effective January 1, 2020, the Company adopted the requirements of Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which requires the measurement and recognition of expected credit losses for financial assets held at amortized cost. ASU 2016-13 replaces the existing incurred loss impairment model with an expected loss model which requires the use of forward-looking information to calculate credit loss estimates. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. These changes will result in earlier recognition of credit losses. The Company adopted ASU 2016-13 effective January 1, 2020 with the cumulative effect of adoption recorded as an adjustment to retained earnings. The effect on its consolidated financial statements and related disclosures is not material. Except for restructuring cost and the impact of the adoption of Topic 326, there have been no changes to the Company’s significant accounting policies described in the Annual Report on Form 10-K for the year ended December 31, 2019 that have had a material impact on the Company’s condensed consolidated financial statements and related notes. Recently Issued and Not Yet Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes that eliminates certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. It also clarifies and simplifies other aspects of the accounting for income taxes. The standard is effective for annual and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption is permitted. The Company is currently evaluating the timing and impact of the adoption of this standard on its consolidated financial statements.

Revenue, Deferred Revenue and D

Revenue, Deferred Revenue and Deferred Commissions	3 Months Ended
Revenue, Deferred Revenue and Deferred Commissions	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue, Deferred Revenue and Deferred Commissions	Revenue, Deferred Revenue and Deferred Commissions Disaggregation of Revenue The Company derives revenue from sale of Software Products, Hardware Products, term contracts, and professional services. All revenue recognized in the condensed consolidated statements of operations is considered to be revenue from contracts with customers. The following table depicts the disaggregation of revenue according to revenue type and is consistent with how the Company evaluates its financial performance (in thousands): Three Months Ended March 31, 2020 2019 Revenue: License Software Products Perpetual license $ 9,359 $ 25,759 Term license 653 324 Hardware Products 4,787 11,597 Subscription Software as a service (“SaaS”) 126 — Support and maintenance 37,400 33,799 Professional services 4,828 4,089 Total revenue $ 57,153 $ 75,568 License Revenue License revenue consists of sales of Software Products and Hardware Products. Software Products are sold with either a perpetual license or a term license. License revenue includes the value allocated to license within Software Products subscription contracts. License revenue is recognized at the time of transfer of control, which is generally upon delivery of access to software downloads or shipment, provided that all other revenue recognition criteria have been met. Subscription Revenue Subscription revenue is derived from support and maintenance contracts, the value allocated to support and maintenance within Software Products subscription contracts, and software-as-a-service (“SaaS”) offering contracts. SaaS customers do not have the right to take possession of the cloud-based software. Subscription contracts have terms that are generally either one or three years, but can be up to five years . Subscription revenue is recognized ratably over the term of the contract and any unearned subscription revenue is included in deferred revenue. Professional Services Revenue Professional services revenue is derived primarily from customer fees for optional installation of the Company’s products or training. Generally, the Company recognizes revenue for professional services as the services are rendered. Revenue from Contracts with Customers Contract Assets and Contract Liabilities A contract asset is a right to consideration in exchange for products or services that the Company has transferred to a customer when that right is conditional and is not just subject to the passage of time. The Company’s payment terms typically range between 30 to 90 days. The Company has no material contract assets. A contract liability is an obligation to transfer products or services for which the Company has received consideration, or for which an amount of consideration is due from the customer. Contract liabilities include customer deposits under non-cancelable contracts included in accrued expenses, and current and non-current deferred revenue balances. The Company’s contract balances are reported in a net contract asset or liability position on a contract-by-contract basis at the end of each reporting period. Significant changes in contract liabilities during the periods presented are as follows (in thousands): Three Months Ended March 31, 2020 Contract Liabilities Balance as of December 31, 2019 $ 188,907 Additions 48,920 Gross revenue recognized (57,153 ) Balance as of March 31, 2020 $ 180,674 During the three months ended March 31, 2020 , the Company recognized revenue of $34.1 million that was included in the contract liabilities balance as of December 31, 2019. During the three months ended March 31, 2019 , the Company recognized revenue of $31.5 million that was included in the contract liabilities balance as of December 31, 2018. Performance Obligations Contracted not recognized revenue was $180.4 million as of March 31, 2020 , of which the Company expects to recognize approximately 62% of the revenue over the next 12 months and the remainder thereafter.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
Fair Value Measurements	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Financial assets are recorded at fair value on the condensed consolidated balance sheets and are categorized based upon the level of judgment associated with inputs used to measure their fair value. The accounting guidance establishes a fair value hierarchy based on the independence of the source and objective evidence of the inputs used. There are three fair value hierarchies based upon the level of inputs that are significant to fair value measurement: • Level 1 —Observable inputs that reflect quoted prices in active markets for identical assets or liabilities. • Level 2 —Observable inputs that reflect quoted prices for identical assets and liabilities in markets that are not active, quoted prices for similar assets or liabilities in active markets, inputs other than quoted prices that are observable for the assets or liabilities, or inputs that are derived principally from or corroborated by observable market data by correlation or other means. • Level 3 —Inputs that are generally unobservable and are supported by little or no market activity, and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability. There have been no transfers between fair value measurement levels during the periods presented. The following table presents the fair value of the Company’s financial assets according to the fair value hierarchy as of March 31, 2020 and December 31, 2019 (in thousands): March 31, 2020 December 31, 2019 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Financial assets Cash and cash equivalents: Cash $ 63,778 $ — $ — $ 62,188 $ — $ — Money market accounts 20,017 — — 6,842 — — Total cash and cash equivalents 83,795 — — 69,030 — — Marketable securities: Commercial paper — — — — 1,998 — Corporate debt securities — 16,126 — — 24,168 — U.S. government securities — — — — 3,015 — Total marketable securities — 16,126 — — 29,181 — Restricted cash (current and non-current) 2,536 — — 2,561 — — Total financial assets $ 86,331 $ 16,126 $ — $ 71,591 $ 29,181 $ —

Marketable Securities

Marketable Securities	3 Months Ended
Marketable Securities	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable Securities The following table summarizes the Company’s marketable securities by significant investment categories as of March 31, 2020 and December 31, 2019 (in thousands): March 31, 2020 December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Amortized Cost Unrealized Gains Fair Value Marketable securities: Available-for-sale: Commercial paper $ — $ — $ — $ — $ 1,998 $ — $ 1,998 Corporate debt securities 16,131 3 (8 ) 16,126 24,122 46 24,168 U.S. government securities — — — — 3,012 3 3,015 Total marketable securities $ 16,131 $ 3 $ (8 ) $ 16,126 $ 29,132 $ 49 $ 29,181 The following table summarizes the amortized cost and fair value of the Company’s available-for-sale securities as of March 31, 2020 and December 31, 2019 by the contractual maturity date (in thousands): March 31, 2020 December 31, 2019 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 16,131 $ 16,126 $ 29,132 $ 29,181 Total $ 16,131 $ 16,126 $ 29,132 $ 29,181 The Company had 5 marketable securities in unrealized loss position as of March 31, 2020 . The Company had no marketable securities in an unrealized loss position as of December 31, 2019 . For individual marketable securities that were in an unrealized loss position as of March 31, 2020 , the fair value and gross unrealized loss for these securities aggregated by investment category and length of time in an unrealized loss position are presented in the following tables (in thousands): March 31, 2020 Less Than 12 Months Greater Than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate debt securities $ 8,058 $ (8 ) $ — $ — $ 8,058 $ (8 ) Total $ 8,058 $ (8 ) $ — $ — $ 8,058 $ (8 ) Unrealized losses related to these marketable securities were immaterial. The effect of COVID-19 on our impairment assessment requires significant judgment due to the uncertainty around the impact. The Company does not intend to sell and it is not likely that the Company would be required to sell these marketable securities before recovery of their amortized cost basis, which may be at maturity.

Restructuring

Restructuring	3 Months Ended
Restructuring	Mar. 31, 2020
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring Q1 2020 Restructuring Plan In the first quarter of fiscal year 2020, the Company initiated a restructuring plan (the “Q1 2020 Restructuring Plan”) as part of the Company’s effort to realign its cost structure in both its go-to-market and engineering organizations. The Q1 2020 Restructuring Plan included reduction in force of approximately 90 employees within the sales, marketing, and engineering functions and was largely completed by March 31, 2020 with no material future costs expected to be incurred. The following table summarizes the activity related to the accrual for restructuring charges (in thousands): Workforce Reduction Cost Accrual balance as at December 31, 2019 $ — Restructuring charges 2,512 Cash payments (1,343 ) Accrual balance as at March 31, 2020 $ 1,169 The accrued restructuring balance as at March 31, 2020

Equity Award Plans

Equity Award Plans	3 Months Ended
Equity Award Plans	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Equity Award Plans	Equity Award Plans Stock-Based Compensation Stock-based compensation expense included in the accompanying condensed consolidated statements of operations is as follows (in thousands): Three Months Ended March 31, 2020 2019 Cost of revenue: License $ 122 $ 83 Subscription 524 443 Professional services 516 401 Research and development 3,683 3,078 Sales and marketing 5,804 6,486 General and administrative 3,209 3,337 Total $ 13,858 $ 13,828 Stock Options The following table summarizes option activity under the Company’s 2000 Stock Option and Incentive Plan and the Company’s 2017 Equity Incentive Plan, and related information (in thousands, except per share and contractual life amounts): Options Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2019 3,066 $ 12.33 5.6 $ 62,759 Options exercised (450 ) $ 11.60 Options forfeited (25 ) $ 20.11 Balance—March 31, 2020 2,591 $ 12.39 5.3 $ 49,762 Options vested and exercisable—March 30, 2020 2,425 $ 11.79 5.2 $ 48,022 As of March 31, 2020 , the total unrecognized compensation cost related to unvested options was $1.6 million , which is expected to be amortized on a straight-line basis over a weighted-average period of approximately 1.1 years. Restricted Stock Units (“RSUs”) and Performance Based Stock Units (“PSUs”) The following table summarizes RSU and PSU activity under the Company’s 2000 Stock Option and Incentive Plan and the Company’s 2017 Equity Incentive Plan (the “2017 Plan”), and related information (in thousands, except per share and contractual life amounts): RSUs and PSUs Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2019 6,391 $ 31.37 1.7 $ 209,621 Granted 178 $ 30.80 Vested (597 ) $ 31.01 Forfeited (476 ) $ 31.94 Balance—March 31, 2020 5,496 $ 31.35 1.6 $ 173,622 The Company has issued PSUs to select executives under the 2017 Plan. The majority of the PSUs vest over a period of four years from the date of grant subject to both the continued employment of the participant with the Company and the achievement of one or more pre-established financial performance goals. Stock-based compensation expense for PSUs is recognized using the accelerated attribution method over the requisite service periods when it is probable that the performance condition will be achieved. As of March 31, 2020 , the total unrecognized compensation cost related to unvested RSUs and PSUs was $134.9 million , which is expected to be amortized over a weighted-average period of approximately 2.6 years.

Income Taxes

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company estimates its annual effective tax rate each quarter and specific events are discretely recognized as they occur under the provisions of ASC 740-270, Income Taxes: Interim Reporting . For the three months ended March 31, 2020 and 2019, the Company recorded a tax provision of $0.4 million and $0.7 million , respectively, representing an effective tax rate of (0.7)% and (2.1)% , respectively. The Company’s effective tax rates for these periods were negative as it has maintained a valuation allowance on the U.S. losses. The key components of the income tax provision primarily consist of foreign income taxes, unrecognized tax benefits, and U.S. state minimum taxes. The effective tax rate increased for the three months ended March 31, 2020 as compared to the three months ended March 31, 2019 primarily due to an increase in worldwide loss before income taxes. The loss was primarily generated in the United States and does not impact the provision for income taxes as it was offset by a full valuation allowance.

Net Loss Per Share

Net Loss Per Share	3 Months Ended
Net Loss Per Share	Mar. 31, 2020
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share Basic net loss per share is computed by dividing net loss by basic weighted-average shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by diluted weighted-average shares outstanding, including potentially dilutive securities, unless anti-dilutive. The following table presents the computation of basic and diluted net loss per share (in thousands, except per share amounts): Three Months Ended March 31, 2020 2019 Net loss $ (61,239 ) $ (34,252 ) Weighted-average shares used to compute net loss per share, basic and diluted 48,593 44,196 Net loss per share, basic and diluted $ (1.26 ) $ (0.78 ) The following securities were excluded from the computation of diluted net loss per share for the periods presented because their inclusion would reduce the net loss per share (in thousands): As of March 31, 2020 2019 Options to purchase common stock 2,591 4,717 Unvested early exercised common shares — 24 Unvested restricted stock units 5,496 5,470 Employee Stock Purchase Plan 196 233

Description of Business and S_2

Description of Business and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) using accounting policies that are consistent with those used in the preparation of the Company’s audited consolidated financial statements for the year ended December 31, 2019 . Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) have been condensed or omitted as permitted by the SEC's rules and regulations. The Company’s condensed consolidated financial statements include the results of Forescout Technologies, Inc. and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated financial statements are unaudited and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, necessary for the fair presentation of the Company’s quarterly results. The condensed consolidated balance sheet as of December 31, 2019 was derived from the audited consolidated financial statements at that date but does not include all the disclosures required by GAAP for the annual financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019 .
Restructuring cost	Restructuring cost The Company records restructuring activities including costs for one-time termination benefits in accordance with ASC Topic 420 (“ASC 420”), Exit or Disposal Cost Obligations. A liability is recognized when management has committed to a restructuring plan and has communicated those actions to employees. Restructuring cost for employee workforce reductions are recorded upon employee notification for employees whose required continuing service period is 60 days or less and ratably over the employee’s continuing service period for employees whose required continuing service period is greater than 60 days . Employee termination benefits covered by existing benefit arrangements are recorded in accordance with ASC Topic 712, Non-retirement Post-employment Benefits.
Credit losses	Credit losses Effective January 1, 2020, the Company adopted the requirements of Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which requires the measurement and recognition of expected credit losses for financial assets held at amortized cost. ASU 2016-13 replaces the existing incurred loss impairment model with an expected loss model which requires the use of forward-looking information to calculate credit loss estimates. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. These changes will result in earlier recognition of credit losses. The Company adopted ASU 2016-13 effective January 1, 2020 with the cumulative effect of adoption recorded as an adjustment to retained earnings. The effect on its consolidated financial statements and related disclosures is not material. Except for restructuring cost and the impact of the adoption of Topic 326, there have been no changes to the Company’s significant accounting policies described in the Annual Report on Form 10-K for the year ended December 31, 2019 that have had a material impact on the Company’s condensed consolidated financial statements and related notes.
Recently Issued and Not Yet Adopted Accounting Pronouncements	Recently Issued and Not Yet Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes that eliminates certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. It also clarifies and simplifies other aspects of the accounting for income taxes. The standard is effective for annual and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption is permitted. The Company is currently evaluating the timing and impact of the adoption of this standard on its consolidated financial statements.
Revenue from Contract with Customer	License Revenue License revenue consists of sales of Software Products and Hardware Products. Software Products are sold with either a perpetual license or a term license. License revenue includes the value allocated to license within Software Products subscription contracts. License revenue is recognized at the time of transfer of control, which is generally upon delivery of access to software downloads or shipment, provided that all other revenue recognition criteria have been met. Subscription Revenue Subscription revenue is derived from support and maintenance contracts, the value allocated to support and maintenance within Software Products subscription contracts, and software-as-a-service (“SaaS”) offering contracts. SaaS customers do not have the right to take possession of the cloud-based software. Subscription contracts have terms that are generally either one or three years, but can be up to five years . Subscription revenue is recognized ratably over the term of the contract and any unearned subscription revenue is included in deferred revenue. Professional Services Revenue Professional services revenue is derived primarily from customer fees for optional installation of the Company’s products or training. Generally, the Company recognizes revenue for professional services as the services are rendered. Disaggregation of Revenue Revenue from Contracts with Customers Contract Assets and Contract Liabilities A contract asset is a right to consideration in exchange for products or services that the Company has transferred to a customer when that right is conditional and is not just subject to the passage of time. The Company’s payment terms typically range between 30 to 90 days. The Company has no material contract assets. A contract liability is an obligation to transfer products or services for which the Company has received consideration, or for which an amount of consideration is due from the customer. Contract liabilities include customer deposits under non-cancelable contracts included in accrued expenses, and current and non-current deferred revenue balances. The Company’s contract balances are reported in a net contract asset or liability position on a contract-by-contract basis at the end of each reporting period.
Fair Value Measurements	Financial assets are recorded at fair value on the condensed consolidated balance sheets and are categorized based upon the level of judgment associated with inputs used to measure their fair value. The accounting guidance establishes a fair value hierarchy based on the independence of the source and objective evidence of the inputs used. There are three fair value hierarchies based upon the level of inputs that are significant to fair value measurement: • Level 1 —Observable inputs that reflect quoted prices in active markets for identical assets or liabilities. • Level 2 —Observable inputs that reflect quoted prices for identical assets and liabilities in markets that are not active, quoted prices for similar assets or liabilities in active markets, inputs other than quoted prices that are observable for the assets or liabilities, or inputs that are derived principally from or corroborated by observable market data by correlation or other means. • Level 3 —Inputs that are generally unobservable and are supported by little or no market activity, and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability.

Revenue, Deferred Revenue and_2

Revenue, Deferred Revenue and Deferred Commissions (Tables)	3 Months Ended
Revenue, Deferred Revenue and Deferred Commissions (Tables)	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table depicts the disaggregation of revenue according to revenue type and is consistent with how the Company evaluates its financial performance (in thousands): Three Months Ended March 31, 2020 2019 Revenue: License Software Products Perpetual license $ 9,359 $ 25,759 Term license 653 324 Hardware Products 4,787 11,597 Subscription Software as a service (“SaaS”) 126 — Support and maintenance 37,400 33,799 Professional services 4,828 4,089 Total revenue $ 57,153 $ 75,568
Contract with Customer, Liability	Significant changes in contract liabilities during the periods presented are as follows (in thousands): Three Months Ended March 31, 2020 Contract Liabilities Balance as of December 31, 2019 $ 188,907 Additions 48,920 Gross revenue recognized (57,153 ) Balance as of March 31, 2020 $ 180,674

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
Fair Value Measurements (Tables)	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Financial Assets	The following table presents the fair value of the Company’s financial assets according to the fair value hierarchy as of March 31, 2020 and December 31, 2019 (in thousands): March 31, 2020 December 31, 2019 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Financial assets Cash and cash equivalents: Cash $ 63,778 $ — $ — $ 62,188 $ — $ — Money market accounts 20,017 — — 6,842 — — Total cash and cash equivalents 83,795 — — 69,030 — — Marketable securities: Commercial paper — — — — 1,998 — Corporate debt securities — 16,126 — — 24,168 — U.S. government securities — — — — 3,015 — Total marketable securities — 16,126 — — 29,181 — Restricted cash (current and non-current) 2,536 — — 2,561 — — Total financial assets $ 86,331 $ 16,126 $ — $ 71,591 $ 29,181 $ —

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
Marketable Securities (Tables)	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Schedule of Amortized Cost, Unrealized Losses, and Fair Value of Marketable Securities	The following table summarizes the Company’s marketable securities by significant investment categories as of March 31, 2020 and December 31, 2019 (in thousands): March 31, 2020 December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Amortized Cost Unrealized Gains Fair Value Marketable securities: Available-for-sale: Commercial paper $ — $ — $ — $ — $ 1,998 $ — $ 1,998 Corporate debt securities 16,131 3 (8 ) 16,126 24,122 46 24,168 U.S. government securities — — — — 3,012 3 3,015 Total marketable securities $ 16,131 $ 3 $ (8 ) $ 16,126 $ 29,132 $ 49 $ 29,181
Investments Classified by Contractual Maturity Date	The following table summarizes the amortized cost and fair value of the Company’s available-for-sale securities as of March 31, 2020 and December 31, 2019 by the contractual maturity date (in thousands): March 31, 2020 December 31, 2019 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 16,131 $ 16,126 $ 29,132 $ 29,181 Total $ 16,131 $ 16,126 $ 29,132 $ 29,181
Schedule of Unrealized Loss on Marketable Securities	For individual marketable securities that were in an unrealized loss position as of March 31, 2020 , the fair value and gross unrealized loss for these securities aggregated by investment category and length of time in an unrealized loss position are presented in the following tables (in thousands): March 31, 2020 Less Than 12 Months Greater Than 12 Months Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate debt securities $ 8,058 $ (8 ) $ — $ — $ 8,058 $ (8 ) Total $ 8,058 $ (8 ) $ — $ — $ 8,058 $ (8 )

Restructuring (Tables)

Restructuring (Tables)	3 Months Ended
Restructuring (Tables)	Mar. 31, 2020
Restructuring and Related Activities [Abstract]
Summary of the Activity Related to the Accrual for Restructuring Charges	The following table summarizes the activity related to the accrual for restructuring charges (in thousands): Workforce Reduction Cost Accrual balance as at December 31, 2019 $ — Restructuring charges 2,512 Cash payments (1,343 ) Accrual balance as at March 31, 2020 $ 1,169

Equity Award Plans (Tables)

Equity Award Plans (Tables)	3 Months Ended
Equity Award Plans (Tables)	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule of Stock-based Compensation Expense for Employees and Non-Employees	Stock-based compensation expense included in the accompanying condensed consolidated statements of operations is as follows (in thousands): Three Months Ended March 31, 2020 2019 Cost of revenue: License $ 122 $ 83 Subscription 524 443 Professional services 516 401 Research and development 3,683 3,078 Sales and marketing 5,804 6,486 General and administrative 3,209 3,337 Total $ 13,858 $ 13,828
Schedule of Option Activity under the Plans	The following table summarizes option activity under the Company’s 2000 Stock Option and Incentive Plan and the Company’s 2017 Equity Incentive Plan, and related information (in thousands, except per share and contractual life amounts): Options Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2019 3,066 $ 12.33 5.6 $ 62,759 Options exercised (450 ) $ 11.60 Options forfeited (25 ) $ 20.11 Balance—March 31, 2020 2,591 $ 12.39 5.3 $ 49,762 Options vested and exercisable—March 30, 2020 2,425 $ 11.79 5.2 $ 48,022
Schedule of RSU Activity under the Plans	The following table summarizes RSU and PSU activity under the Company’s 2000 Stock Option and Incentive Plan and the Company’s 2017 Equity Incentive Plan (the “2017 Plan”), and related information (in thousands, except per share and contractual life amounts): RSUs and PSUs Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2019 6,391 $ 31.37 1.7 $ 209,621 Granted 178 $ 30.80 Vested (597 ) $ 31.01 Forfeited (476 ) $ 31.94 Balance—March 31, 2020 5,496 $ 31.35 1.6 $ 173,622
Schedule of PSU Activity under the Plans	The following table summarizes RSU and PSU activity under the Company’s 2000 Stock Option and Incentive Plan and the Company’s 2017 Equity Incentive Plan (the “2017 Plan”), and related information (in thousands, except per share and contractual life amounts): RSUs and PSUs Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2019 6,391 $ 31.37 1.7 $ 209,621 Granted 178 $ 30.80 Vested (597 ) $ 31.01 Forfeited (476 ) $ 31.94 Balance—March 31, 2020 5,496 $ 31.35 1.6 $ 173,622

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
Net Loss Per Share (Tables)	Mar. 31, 2020
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Net Loss Per Share	The following table presents the computation of basic and diluted net loss per share (in thousands, except per share amounts): Three Months Ended March 31, 2020 2019 Net loss $ (61,239 ) $ (34,252 ) Weighted-average shares used to compute net loss per share, basic and diluted 48,593 44,196 Net loss per share, basic and diluted $ (1.26 ) $ (0.78 )
Schedule of Securities Excluded from Computation of Diluted Net Loss Per Share	The following securities were excluded from the computation of diluted net loss per share for the periods presented because their inclusion would reduce the net loss per share (in thousands): As of March 31, 2020 2019 Options to purchase common stock 2,591 4,717 Unvested early exercised common shares — 24 Unvested restricted stock units 5,496 5,470 Employee Stock Purchase Plan 196 233

Description of Business and S_3

Description of Business and Summary of Significant Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2020product	Feb. 06, 2020$ / shares
Business Acquisition [Line Items]
Number of product groups	2
Number of product types	2
Deferred compensation arrangement with individual, service period (in days)	60 days
Ferrari Group Holdings, L.P. \| Forescout Technologies, Inc.
Business Acquisition [Line Items]
Payment by affiliate (in USD per share) \| $ / shares		$ 33

Revenue, Deferred Revenue and_3

Revenue, Deferred Revenue and Deferred Commissions - Disaggregation of Revenue According to Revenue Type (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 57,153	$ 75,568
Perpetual license
Disaggregation of Revenue [Line Items]
Revenue	9,359	25,759
Term license
Disaggregation of Revenue [Line Items]
Revenue	653	324
Hardware products
Disaggregation of Revenue [Line Items]
Revenue	4,787	11,597
Software as a service (“SaaS”)
Disaggregation of Revenue [Line Items]
Revenue	126	0
Support and maintenance
Disaggregation of Revenue [Line Items]
Revenue	37,400
Professional services
Disaggregation of Revenue [Line Items]
Revenue	$ 4,828	$ 4,089

Revenue, Deferred Revenue and_4

Revenue, Deferred Revenue and Deferred Commissions - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with customer, asset	$ 0
Contract with customer, performance obligation satisfied in previous period	$ 34,100,000	$ 31,500,000
Support and maintenance
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, performance obligation, description of timing	terms that are generally either one or three years, but can be up to five years

Revenue, Deferred Revenue and_5

Revenue, Deferred Revenue and Deferred Commissions - Significant Changes in Contract Liabilities (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Change In Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 188,907
Additions	48,920
Gross revenue recognized	(57,153)
Ending balance	$ 180,674

Revenue, Deferred Revenue and_6

Revenue, Deferred Revenue and Deferred Commissions - Performance Obligations (Details) $ in Millions	Mar. 31, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation	$ 180.4
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, percentage	62.00%
Performance obligation expected to be satisfied, expected timing	12 months

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 16,126	$ 29,181
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	1,998
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	16,126	24,168
U.S. government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	3,015
Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	83,795	69,030
Marketable securities	0	0
Restricted cash (current and non-current)	2,536	2,561
Total financial assets	86,331	71,591
Recurring \| Level 1 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Recurring \| Level 1 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Recurring \| Level 1 \| U.S. government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Recurring \| Level 1 \| Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	63,778	62,188
Recurring \| Level 1 \| Money market accounts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	20,017	6,842
Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Marketable securities	16,126	29,181
Restricted cash (current and non-current)	0	0
Total financial assets	16,126	29,181
Recurring \| Level 2 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	1,998
Recurring \| Level 2 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	16,126	24,168
Recurring \| Level 2 \| U.S. government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	3,015
Recurring \| Level 2 \| Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring \| Level 2 \| Money market accounts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Marketable securities	0	0
Restricted cash (current and non-current)	0	0
Total financial assets	0	0
Recurring \| Level 3 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Recurring \| Level 3 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Recurring \| Level 3 \| U.S. government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Recurring \| Level 3 \| Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring \| Level 3 \| Money market accounts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 0	$ 0

Marketable Securities - Summary

Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 16,131	$ 29,132
Unrealized Gains	3	49
Unrealized Losses	(8)
Fair Value	16,126	29,181
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	1,998
Unrealized Gains	0	0
Unrealized Losses	0
Fair Value	0	1,998
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,131	24,122
Unrealized Gains	3	46
Unrealized Losses	(8)
Fair Value	16,126	24,168
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	3,012
Unrealized Gains	0	3
Unrealized Losses	0
Fair Value	$ 0	$ 3,015

Marketable Securities - Maturit

Marketable Securities - Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized Cost
Due within one year	$ 16,131	$ 29,132
Amortized Cost	16,131	29,132
Fair Value
Due within one year	16,126	29,181
Fair Value	$ 16,126	$ 29,181

Marketable Securities - Narrati

Marketable Securities - Narrative (Details) - security	Mar. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Number of marketable securities in unrealized loss positions	5	0

Marketable Securities - Continu

Marketable Securities - Continuous Unrealized Loss Position (Details) $ in Thousands	Mar. 31, 2020USD ($)
Fair Value
Less Than 12 Months	$ 8,058
Greater Than 12 Months	0
Total	8,058
Unrealized Loss
Less Than 12 Months	(8)
Greater Than 12 Months	0
Total	(8)
Corporate debt securities
Fair Value
Less Than 12 Months	8,058
Greater Than 12 Months	0
Total	8,058
Unrealized Loss
Less Than 12 Months	(8)
Greater Than 12 Months	0
Total	$ (8)

Restructuring - Narrative (Deta

Restructuring - Narrative (Details)	3 Months Ended
Restructuring - Narrative (Details)	Mar. 31, 2020employee
Q1 2020 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated	90

Restructuring - Accrual of Rest

Restructuring - Accrual of Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Restructuring Reserve [Roll Forward]
Restructuring charges	$ 2,512	$ 0
Q1 2020 Restructuring Plan
Restructuring Reserve [Roll Forward]
Accrual balance	0
Restructuring charges	2,512
Cash payments	(1,343)
Accrual balance	$ 1,169

Equity Award Plans - Stock-base

Equity Award Plans - Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 13,858	$ 13,828
License
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	122	83
Subscription
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	524	443
Professional services
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	516	401
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	3,683	3,078
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	5,804	6,486
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 3,209	$ 3,337

Equity Award Plans - Option Act

Equity Award Plans - Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Number of Shares
Balance beginning of the period (shares)	3,066,000
Options exercised (shares)	(450,000)
Options forfeited (shares)	(25,000)
Balance end of the period (shares)	2,591,000	3,066,000
Options vested and exercisable at end of period (shares)	2,425,000
Weighted- Average Exercise Price
Balance beginning of the period (in dollars per share)	$ 12.33
Options exercised (in dollars per share)	11.60
Options forfeited (in dollars per share)	20.11
Balance end of the period (in dollars per share)	12.39	$ 12.33
Options vested and exercisable at end of period (in dollars per share)	$ 11.79
Weighted- Average Remaining Contractual Life (Years)
Balance	5 years 3 months 18 days	5 years 7 months 6 days
Options vested and exercisable	5 years 2 months 12 days
Aggregate Intrinsic Value
Balance	$ 49,762	$ 62,759
Options vested and exercisable	$ 48,022

Equity Award Plans - Narrative

Equity Award Plans - Narrative (Details) $ in Millions	3 Months Ended
Equity Award Plans - Narrative (Details) $ in Millions	Mar. 31, 2020USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested options	$ 1.6
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Straight-line basis weighted-average amortization period	1 year 1 month 6 days
RSUs and PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Straight-line basis weighted-average amortization period	2 years 7 months 6 days
Unrecognized compensation cost	$ 134.9
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years

Equity Award Plans - RSU and PS

Equity Award Plans - RSU and PSU Activity (Details) - RSUs and PSUs - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Number of Shares
Balance at beginning of period (in shares)	6,391,000
Granted (in shares)	178,000
Vested (in shares)	(597,000)
Forfeited (in shares)	(476,000)
Balance at end of period (in shares)	5,496,000	6,391,000
Weighted- Average Grant Date Fair Value Per Share
Balance at beginning of period (in dollars per share)	$ 31.37
RSUs granted (in dollars per share)	30.80
RSUs vested (in dollars per share)	31.01
RSUs forfeited (in dollars per share)	31.94
Balance at end of period (in dollars per share)	$ 31.35	$ 31.37
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures
Weighted- Average Remaining Contractual Life (Years)	1 year 7 months 6 days	1 year 8 months 12 days
Aggregate Intrinsic Value	$ 173,622	$ 209,621

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income tax provision	$ 432	$ 711
Effective tax rate	(0.70%)	(2.10%)

Net Loss Per Share - Basic and

Net Loss Per Share - Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net loss	$ (61,239)	$ (34,252)
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)	48,593	44,196
Net loss per share, basic and diluted (in dollars per share)	$ (1.26)	$ (0.78)

Net Loss Per Share - Securities

Net Loss Per Share - Securities Excluded from Diluted Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share (in shares)	2,591	4,717
Unvested early exercised common shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share (in shares)	0	24
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share (in shares)	5,496	5,470
Employee Stock Purchase Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share (in shares)	196	233

Uncategorized Items - forescout

Label	Element	Value
Restricted Cash and Cash Equivalents, Current	us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue	$ 852,000
Restricted Cash and Cash Equivalents, Current	us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue	$ 1,006,000