Income Taxes - Reconciliation of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Tax expense at statutory rate of 34%	$ 4,427	$ 4,354	$ 12,757
Tax expense (benefit), statutory rate	34.00%	34.00%	34.00%
State income taxes, net of federal benefit	$ (50)	$ 54	$ 425
Foreign tax rate difference	(1,939)	(3,708)	(2,917)
Research and development credit	(917)	(853)	(583)
Change in valuation allowance	162	(28)	(5,392)
Equity based compensation	(255)	54	880
Manufacturing credit	(61)	11	(721)
Other	152	109	(576)
Income tax expense (benefit)	$ 1,519	$ (7)	$ 3,873