Condensed Consolidated Statements of Changes in 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		38,466
Beginning balance at Dec. 31, 2018	$ 71,002	$ 385	$ 239,865	$ (168,140)	$ (1,108)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	9,949			9,949
Other comprehensive income (loss)	56				56
Stock option exercises and employee stock plan purchases (in shares)		37
Stock option exercises and employee stock plan purchases	606	$ 0	606
Vesting of restricted stock awards and units (in shares)		365
Vesting of restricted stock awards and units	0	$ 4	(4)
Shares withheld to cover taxes (in shares)		(50)
Shares withheld to cover taxes	(1,120)	$ (1)	(1,119)
Stock-based compensation	2,720		2,720
Ending balance (in shares) at Mar. 31, 2019		38,818
Ending balance at Mar. 31, 2019	83,213	$ 388	242,068	(158,191)	(1,052)
Beginning balance (in shares) at Dec. 31, 2018		38,466
Beginning balance at Dec. 31, 2018	71,002	$ 385	239,865	(168,140)	(1,108)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	16,361
Other comprehensive income (loss)	144
Ending balance (in shares) at Jun. 30, 2019		39,043
Ending balance at Jun. 30, 2019	92,247	$ 390	244,600	(151,779)	(964)
Beginning balance (in shares) at Mar. 31, 2019		38,818
Beginning balance at Mar. 31, 2019	83,213	$ 388	242,068	(158,191)	(1,052)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	6,412			6,412
Other comprehensive income (loss)	88				88
Stock option exercises and employee stock plan purchases (in shares)		9
Stock option exercises and employee stock plan purchases	120	$ 0	120
Vesting of restricted stock awards and units (in shares)		253
Vesting of restricted stock awards and units	0	$ 3	(3)
Shares withheld to cover taxes (in shares)		(37)
Shares withheld to cover taxes	(944)	$ (1)	(943)
Stock-based compensation	3,358		3,358
Ending balance (in shares) at Jun. 30, 2019		39,043
Ending balance at Jun. 30, 2019	92,247	$ 390	244,600	(151,779)	(964)
Beginning balance (in shares) at Dec. 31, 2019		39,251
Beginning balance at Dec. 31, 2019	114,601	$ 393	251,641	(136,473)	(960)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	3,337			3,337
Other comprehensive income (loss)	(1,434)				(1,434)
Stock option exercises and employee stock plan purchases (in shares)		33
Stock option exercises and employee stock plan purchases	366	$ 0	366
Vesting of restricted stock awards and units (in shares)		563
Vesting of restricted stock awards and units	0	$ 6	(6)
Shares withheld to cover taxes (in shares)		(97)
Shares withheld to cover taxes	(1,547)	$ (1)	(1,546)
Stock-based compensation	3,075		3,075
Ending balance (in shares) at Mar. 31, 2020		39,750
Ending balance at Mar. 31, 2020	118,398	$ 398	253,530	(133,136)	(2,394)
Beginning balance (in shares) at Dec. 31, 2019		39,251
Beginning balance at Dec. 31, 2019	114,601	$ 393	251,641	(136,473)	(960)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(3,675)
Other comprehensive income (loss)	(1,646)
Ending balance (in shares) at Jun. 30, 2020		66,808
Ending balance at Jun. 30, 2020	515,583	$ 668	657,669	(140,148)	(2,606)
Beginning balance (in shares) at Mar. 31, 2020		39,750
Beginning balance at Mar. 31, 2020	118,398	$ 398	253,530	(133,136)	(2,394)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(7,012)			(7,012)
Other comprehensive income (loss)	(212)				(212)
Stock option exercises and employee stock plan purchases (in shares)		7
Stock option exercises and employee stock plan purchases	50	$ 0	50
Vesting of restricted stock awards and units (in shares)		242
Vesting of restricted stock awards and units	0	$ 2	(2)
Shares withheld to cover taxes (in shares)		(36)
Shares withheld to cover taxes	(485)	$ (1)	(484)
Issuance of common stock (in shares)		26,845
Issuance of common stock, net of $3,776 issuance costs	394,334	$ 269	394,065
Fair value of replacement options related to pre-acquisition services	7,125		7,125
Stock-based compensation	3,385		3,385
Ending balance (in shares) at Jun. 30, 2020		66,808
Ending balance at Jun. 30, 2020	$ 515,583	$ 668	$ 657,669	$ (140,148)	$ (2,606)