Income Taxes - Pre-tax Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Domestic operations	$ 165	$ (6,857)	$ (2,793)
Foreign operations	25,023	42,832	43,244
Income before provision for income taxes	$ 25,188	$ 35,975	$ 40,451