Statement of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Total
Increase (Decrease) in Stockholders' Equity
Adoption of ASU 2016-09 (see Note 1) | Accounting Standard Update 2016 09		$ 401		$ (401)
Balance, restated	$ 466	553,290	$ (1,441)	(238,361)	$ 313,954
Balance (Scenario, Previously Reported) at Dec. 31, 2016	$ 466	552,889	(1,441)	(237,960)	313,954
Balance at Dec. 31, 2016					313,954
Balance (in shares) (Scenario, Previously Reported) at Dec. 31, 2016	46,567,978
Balance (in shares) at Dec. 31, 2016	46,567,978
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise and vesting of stock awards	$ 1	1,025			1,026
Issuance of common stock upon exercise and vesting of stock awards (in shares)	121,469
Comprehensive income (loss)			245	(14,635)	(14,390)
Stock-based compensation expense		3,158			3,158
Balance at Mar. 31, 2017	$ 467	$ 557,473	$ (1,196)	$ (252,996)	$ 303,748
Balance (in shares) at Mar. 31, 2017	46,689,447