Long-Lived Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Client contracts
Summary of carrying value of assets
Gross Carrying Amount	$ 127,628	$ 135,488
Accumulated Amortization	(87,890)	(88,585)
Net Amount	39,738	46,903
Client contracts | Investments in client contracts
Summary of carrying value of assets
Gross Carrying Amount	25,176	34,657
Accumulated Amortization	(17,060)	(23,907)
Net Amount	8,116	10,750
Client contracts | Capitalized costs
Summary of carrying value of assets
Gross Carrying Amount	10,868	6,667
Accumulated Amortization	(2,489)	(3,463)
Net Amount	8,379	3,204
Client contracts | Acquired client contracts
Summary of carrying value of assets
Gross Carrying Amount	91,584	94,164
Accumulated Amortization	(68,341)	(61,215)
Net Amount	23,243	32,949
Software
Summary of carrying value of assets
Gross Carrying Amount	130,189	131,529
Accumulated Amortization	(95,094)	(86,797)
Net Amount	35,095	44,732
Software | Acquired software
Summary of carrying value of assets
Gross Carrying Amount	66,798	67,012
Accumulated Amortization	(61,475)	(56,806)
Net Amount	5,323	10,206
Software | Internal use software
Summary of carrying value of assets
Gross Carrying Amount	63,391	64,517
Accumulated Amortization	(33,619)	(29,991)
Net Amount	$ 29,772	$ 34,526