CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2018		94,465,440
Beginning balance at Dec. 31, 2018	$ 320,443	$ 94	$ 340,291	$ (579)	$ (19,363)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuance ESPP Plan (in shares)		36,032
Common stock issuance ESPP Plan	419		419
Stock issuance fees and expenses	(66)		(66)
Loss on effective cash flow hedges	(557)			(557)
Issuance of restricted stock, net of forfeitures (in shares)		182,502
Issuance of common stock for stock options (in shares)		619,536
Issuance of common stock for stock options	3,894	$ 1	3,893
ESPP expense	119		119
Stock based compensation expense - options and restricted stock	2,020		2,020
NET LOSS	(2,424)				(2,424)
Ending balance (in shares) at Mar. 31, 2019		95,303,510
Ending balance at Mar. 31, 2019	323,848	$ 95	346,676	(1,136)	(21,787)
Beginning balance (in shares) at Dec. 31, 2019		104,781,236
Beginning balance at Dec. 31, 2019	507,408	$ 105	520,278	(1,618)	(11,357)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuance ESPP Plan (in shares)		34,330
Common stock issuance ESPP Plan	796		796
Stock issuance fees and expenses	(15)		(15)
Loss on effective cash flow hedges	(1,038)			(1,038)
Issuance of restricted stock, net of forfeitures (in shares)		76,618
Issuance of restricted stock, net of forfeitures	$ (212)		(212)
Issuance of common stock for stock options (in shares)	504,127	503,873
Issuance of common stock for stock options	$ 2,897		2,897
ESPP expense	194		194
Stock based compensation expense - options and restricted stock	1,991		1,991
NET LOSS	(6,978)				(6,978)
Ending balance (in shares) at Mar. 31, 2020		105,396,057
Ending balance at Mar. 31, 2020	$ 505,043	$ 105	$ 525,929	$ (2,656)	$ (18,335)