Condensed Consolidated Statements of Changes in Stockholders' Deficit Statement - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	[1]	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Cumulative Effect, Period of Adoption, Adjustment	[1]	Other Comprehensive Loss	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	[1]
Balance at beginning (in shares) at Dec. 31, 2020				44,441
Balance at beginning at Dec. 31, 2020	$ 306,948	$ (51,012)		$ 4	$ 848,891	$ (58,543)		$ 83	$ (542,030)	$ 7,531
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued for stock options and restricted stock units (in shares)				726
Common stock issued for stock options and restricted stock units	2,250			$ 1	2,249
Common stock issued for employee stock purchase plan (in shares)				38
Common stock issued for employee stock purchase plan	1,192				1,192
Tax withholdings related to net share settlements of restricted stock units	(2,585)				(2,585)
Stock-based compensation	7,385				7,385
Net loss	(27,712)								(27,712)
Other comprehensive loss	(74)							(74)
Balance at end (in shares) at Mar. 31, 2021				45,205
Balance at end at Mar. 31, 2021	236,392			$ 5	798,589			9	(562,211)
Balance at beginning (in shares) at Dec. 31, 2021				45,729
Balance at beginning at Dec. 31, 2021	176,962			$ 5	827,028			(318)	(649,753)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued for stock options and restricted stock units (in shares)				624
Common stock issued for stock options and restricted stock units	1,035			$ 0	1,035
Common stock issued for employee stock purchase plan (in shares)				49
Common stock issued for employee stock purchase plan	1,502				1,502
Tax withholdings related to net share settlements of restricted stock units	(1,505)				(1,505)
Stock-based compensation	7,785				7,785
Net loss	(39,500)								(39,500)
Other comprehensive loss	(974)							(974)
Balance at end (in shares) at Mar. 31, 2022				46,402
Balance at end at Mar. 31, 2022	$ 145,305			$ 5	$ 835,845			$ (1,292)	$ (689,253)

[1] (1) Effective January 1, 2021, the Company adopted Accounting Standard Update No. 2020-06, Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (Subtopic 815-40). See Note 2. Basis of Presentation and Summary of Significant Accounting Policies and Note 9. Long-term Debt, Net for more information.