Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity - USD ($) $ in Thousands	Total	Adjustment for impact of accounting standard	Series A Redeemable Convertible Preferred Stock	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Adjustment for impact of accounting standard	Accumulated Other Comprehensive Income	Accumulated Deficit	Accumulated Deficit Adjustment for impact of accounting standard
Preferred stock, beginning balance (in shares) at Dec. 31, 2017			6,864,000
Preferred stock, beginning balance at Dec. 31, 2017			$ 32,615
Increase (Decrease) in Temporary Equity [Roll Forward]
Redemption of Series A Preferred stock (in shares)			(6,864,000)
Redemption of Series A Preferred Stock	$ (21,348)		$ (37,823)		$ (21,348)
Deemed dividends on preferred stock and amortization of beneficial conversion feature	(5,208)		$ 5,208		(5,208)
Issuance of restricted stock, net of forfeitures (in shares)				62,182
Issuance of restricted stock, net of forfeitures	$ (297)				(297)
Issuance of common stock for stock options (in shares)	1,570,211			1,553,544
Issuance of common stock for stock options	$ 8,598			$ 2	8,596
Preferred stock, ending balance (in shares) at Dec. 31, 2018			0
Preferred stock, ending balance at Dec. 31, 2018			$ 0
Stockholders' equity, beginning balance (in shares) at Dec. 31, 2017				80,462,574
Stockholders' equity, beginning balance at Dec. 31, 2017	$ 171,962	$ 35		$ 80	194,687	$ (1,095)	$ 274	$ (23,079)	$ 1,130
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuance ESPP plan (in shares)	113,503			117,146
Common stock issuance ESPP plan	$ 1,050				1,050
Stock issuance fees and expenses	(354)				(354)
Loss on effective cash flow hedge	(785)						(785)
Issuance of common stock - Acquisition (in shares)				999,994
Issuance of common stock - Acquisition	13,243			$ 1	13,242
Issuance of common stock - public offering, net of underwriting discounts (in shares)				11,270,000
Issuance of common stock - public offering, net of underwriting discounts	135,071			$ 11	135,060
Gain on redemption of preferred stock	9,075				9,075
Working capital adjustment related to acquisition	0
Foreign currency translation adjustments	(122)						(68)	(54)
Unrealized loss on securities, net	0
ESPP Expense	243				243
Stock compensation expense - options and restricted stock	6,640				6,640
Net income (loss)	2,640							2,640
Stockholders' equity, ending balance (in shares) at Dec. 31, 2018				94,465,440
Stockholders' equity, ending balance at Dec. 31, 2018	320,443			$ 94	340,291		(579)	(19,363)
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of restricted stock, net of forfeitures (in shares)				168,501
Issuance of restricted stock, net of forfeitures	$ (837)				(837)
Issuance of common stock for stock options (in shares)	2,309,451			2,054,911
Issuance of common stock for stock options	$ 9,974			$ 3	9,971
Preferred stock, ending balance (in shares) at Dec. 31, 2019			0
Preferred stock, ending balance at Dec. 31, 2019			$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuance ESPP plan (in shares)	141,908			141,908
Common stock issuance ESPP plan	$ 2,332				2,332
Stock issuance fees and expenses	(263)				(263)
Loss on effective cash flow hedge	(1,039)						(1,039)
Issuance of common stock - public offering, net of underwriting discounts (in shares)				8,050,000
Issuance of common stock - public offering, net of underwriting discounts	160,774			$ 8	160,766
Working capital adjustment related to acquisition (in shares)				(99,524)
Working capital adjustment related to acquisition	(1,977)				(1,977)
Unrealized loss on securities, net	0
ESPP Expense	609				609
Stock compensation expense - options and restricted stock	9,386				9,386
Net income (loss)	8,006							8,006
Stockholders' equity, ending balance (in shares) at Dec. 31, 2019				104,781,236
Stockholders' equity, ending balance at Dec. 31, 2019	507,408			$ 105	520,278		(1,618)	(11,357)
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of restricted stock, net of forfeitures (in shares)			0	97,478
Issuance of restricted stock, net of forfeitures	$ (1,276)				(1,276)
Issuance of common stock for stock options (in shares)	2,310,934		0	2,306,951
Issuance of common stock for stock options	$ 18,275		$ 0	$ 2	18,273
Preferred stock, ending balance (in shares) at Dec. 31, 2020			0
Preferred stock, ending balance at Dec. 31, 2020			$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuance ESPP plan (in shares)	138,309		0	138,309
Common stock issuance ESPP plan	$ 3,579				3,579
Stock issuance fees and expenses	(268)				(268)
Loss on effective cash flow hedge	(1,000)						(1,000)
Cash flow hedge termination reclassified to earnings	2,661						2,661
Issuance of common stock - public offering, net of underwriting discounts (in shares)				4,751,500
Issuance of common stock - public offering, net of underwriting discounts	127,293			$ 5	127,288
Working capital adjustment related to acquisition	0
Unrealized loss on securities, net	(33)						(33)
ESPP Expense	875				875
Stock compensation expense - options and restricted stock	9,337				9,337
Equity component of Convertible Senior Notes due 2025	30,912				30,912
Tax liability related to Convertible Senior Notes due 2025	(7,504)				(7,504)
Convertible note debt issuance costs	(137)				(137)
Net income (loss)	4,172							4,172
Stockholders' equity, ending balance (in shares) at Dec. 31, 2020				112,075,474
Stockholders' equity, ending balance at Dec. 31, 2020	$ 694,294			$ 112	$ 701,357		$ 10	$ (7,185)