Goodwill and Identifiable Intangible Assets - Schedule of Finite-lived and Indefinite-lived Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Finite-lived and Indefinite-lived Intangible Assets [Line Items]
Accumulated Amortization	$ (214,269)	$ (176,303)
Total	381,279
Gross Carrying Amount, Trade names (unamortized)	170,218	170,218
Accumulated Impairment Charge, Trade names (unamortized)	(49,437)	(47,966)
Total, Trade names (unamortized)	120,781	122,252
Gross Carrying Amount, Total	770,600	770,600
Accumulated Impairment Charge, Total	(54,271)	(52,800)
Total	502,060	541,497
Contract backlog
Schedule of Finite-lived and Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	47,620	47,620
Accumulated Amortization	(47,620)	(47,583)
Accumulated Impairment Charge	0	0
Total	0	37
Developed technology/Vendor network
Schedule of Finite-lived and Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	95,661	95,661
Accumulated Amortization	(35,347)	(30,212)
Accumulated Impairment Charge	0	0
Total	60,314	65,449
Customer relationships
Schedule of Finite-lived and Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	425,873	425,873
Accumulated Amortization	(112,457)	(83,391)
Accumulated Impairment Charge	(4,834)	(4,834)
Total	308,582	337,648
Non-competition agreements
Schedule of Finite-lived and Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	9,980	9,980
Accumulated Amortization	(9,330)	(8,498)
Accumulated Impairment Charge	0	0
Total	650	1,482
Trade names (amortized)
Schedule of Finite-lived and Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	21,248	21,248
Accumulated Amortization	(9,515)	(6,619)
Accumulated Impairment Charge	0	0
Total	$ 11,733	$ 14,629