Amortization Expense of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense – cost of revenue	$ 4,164	$ 4,712	$ 6,143
Amortization expense – operating expenses	8,251	7,611	10,262
Total amortization expense	$ 12,415	$ 12,323	$ 16,405