Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2018		40,863
Beginning balance at Dec. 31, 2018	$ 79,755	$ 41	$ 313,800	$ (234,086)	$ 0
Increase (Decrease) in Stockholders' Equity [Rollforward]
Sale of common stock in a public offering, net of offering costs (in shares)		6,325
Sale of common stock in a public offering, net of offering costs	137,848	$ 6	137,842
Issuance of common stock for acquisition (in shares)		377
Issuance of common stock for acquisition	10,000	$ 1	9,999
Issuance of common stock on exercise of stock options and vesting of restricted stock units (in shares)		1,924
Issuance of common stock on exercise of stock options and vesting of restricted stock units	14,355	$ 2	14,353
Issuance of common stock under employee stock purchase plan (ESPP) (in shares)		136
Issuance of common stock under employee stock purchase plan (ESPP)	1,266		1,266
Tax portion of vested restricted stock units	(977)		(977)
Stock-based compensation expense (employee)	8,883		8,883
Stock-based compensation expense (non-employee)	181		181
Stock-based compensation expense (ESPP)	743		743
Net loss	(12,599)			(12,599)
Ending balance (in shares) at Dec. 31, 2019		49,625
Ending balance at Dec. 31, 2019	239,455	$ 50	486,090	(246,685)	0
Increase (Decrease) in Stockholders' Equity [Rollforward]
Sale of common stock in a public offering, net of offering costs (in shares)		6,900
Sale of common stock in a public offering, net of offering costs	193,831	$ 7	193,824
Issuance of common stock on exercise of stock options and vesting of restricted stock units (in shares)		1,573
Issuance of common stock on exercise of stock options and vesting of restricted stock units	11,668	$ 1	11,667
Issuance of common stock under employee stock purchase plan (ESPP) (in shares)		103
Issuance of common stock under employee stock purchase plan (ESPP)	2,037		2,037
Tax portion of vested restricted stock units	(3,845)		(3,845)
Stock-based compensation expense (employee)	12,017		12,017
Stock-based compensation expense (non-employee)	51		51
Stock-based compensation expense (ESPP)	927		927
Net loss	(34,909)			(34,909)
Ending balance (in shares) at Dec. 31, 2020		58,201
Ending balance at Dec. 31, 2020	421,232	$ 58	702,768	(281,594)	0
Increase (Decrease) in Stockholders' Equity [Rollforward]
Sale of common stock in a public offering, net of offering costs (in shares)		8,547
Sale of common stock in a public offering, net of offering costs	593,821	$ 9	593,812
Issuance of common stock for acquisition (in shares)		3,347
Issuance of common stock for acquisition	147,089	$ 3	147,086
Issuance of common stock on exercise of stock options and vesting of restricted stock units (in shares)		947
Issuance of common stock on exercise of stock options and vesting of restricted stock units	9,175	$ 1	9,174
Issuance of common stock under employee stock purchase plan (ESPP) (in shares)		81
Issuance of common stock under employee stock purchase plan (ESPP)	2,353		2,353
Tax portion of vested restricted stock units	(9,029)		(9,029)
Stock-based compensation expense (employee)	20,795		20,795
Stock-based compensation expense (non-employee)	61		61
Stock-based compensation expense (ESPP)	1,663		1,663
Net loss	(75,563)			(75,563)
Other comprehensive loss	(15,083)				(15,083)
Ending balance (in shares) at Dec. 31, 2021		71,123
Ending balance at Dec. 31, 2021	$ 1,096,514	$ 71	$ 1,468,683	$ (357,157)	$ (15,083)