Commitments and Contingencies - Lease Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Operating lease rent expense	$ 3,700	$ 3,200	$ 2,500
Capital leased assets	39,850	40,806
Computer Equipment and Furniture
Property, Plant and Equipment [Line Items]
Capital leased assets	$ 500	$ 1,700	$ 1,700