Software and Other Intangible Assets - Carrying Amount and Accumulated Amortization of Other Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 365,225	$ 349,184
Accumulated Amortization	(108,300)	(87,748)
Net Balance	256,925	261,436
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	336,075	322,216
Accumulated Amortization	(86,585)	(68,616)
Net Balance	249,490	253,600
Trademarks and tradenames [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	18,040	15,767
Accumulated Amortization	(10,605)	(7,946)
Net Balance	7,435	7,821
Purchased contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,690	10,768
Accumulated Amortization	(10,690)	(10,768)
Covenant not to compete [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	420	433
Accumulated Amortization	$ (420)	(418)
Net Balance		$ 15