Long-Lived Assets - Summary of Carrying Value of Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 259,641	$ 267,141
Accumulated Amortization	(191,624)	(196,039)
Net Amount	68,017	71,102
Client contracts
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	128,501	137,398
Accumulated Amortization	(89,935)	(96,723)
Net Amount	38,566	40,675
Software
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	131,140	129,743
Accumulated Amortization	(101,689)	(99,316)
Net Amount	$ 29,451	$ 30,427