Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets and liabilities:
Accruals and prepaids	$ 4,992	$ 4,606
Intangible assets	(5,130)	146
Property and equipment	(1,338)	(1,396)
R&D and other tax credits	1,219	3,293
Stock Compensation	7,417	7,063
Net operating loss	2,395	1,763
Other	113	145
Net deferred tax assets	9,668	15,620
Valuation allowance	(554)	(782)
Deferred tax assets and liabilities, net of valuation allowance	$ 9,114	$ 14,838