Acquisitions - Purchase Price Allocation of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets	$ 214,313
All 2012 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets		109,758
Customer Relationships [Member] | All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets	161,123
Customer Relationships [Member] | All 2013 Acquisitions [Member] | Minimum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	3 years
Customer Relationships [Member] | All 2013 Acquisitions [Member] | Maximum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	20 years
Customer Relationships [Member] | All 2012 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets		77,654
Customer Relationships [Member] | All 2012 Acquisitions [Member] | Minimum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		10 years
Customer Relationships [Member] | All 2012 Acquisitions [Member] | Maximum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		20 years
Trade Names And Trademarks-Indefinite [Member] | All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	15 years
Intangible assets	200
Merchant Network [Member] | All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	10 years
Intangible assets	4,900
Merchant Network [Member] | All 2012 Acquisitions [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		10 years
Intangible assets		4,604
Software [Member] | All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets	13,090
Software [Member] | All 2013 Acquisitions [Member] | Minimum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	3 years
Software [Member] | All 2013 Acquisitions [Member] | Maximum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	10 years
Software [Member] | All 2012 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets		9,800
Software [Member] | All 2012 Acquisitions [Member] | Minimum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		3 years
Software [Member] | All 2012 Acquisitions [Member] | Maximum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		10 years
Non-compete [Member] | Minimum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	2 years	2 years
Non-compete [Member] | Maximum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	6 years	6 years
Non-compete [Member] | All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)	6 years
Intangible assets	15,000
Non-compete [Member] | All 2012 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets		800
Non-compete [Member] | All 2012 Acquisitions [Member] | Minimum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		2 years
Non-compete [Member] | All 2012 Acquisitions [Member] | Maximum [Member]
Business Acquisition [Line Items]
Weighted Average Useful Lives (in Years)		6 years
Trade names and trademarks-indefinite [Member] | All 2013 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets	20,000
Trade names and trademarks-indefinite [Member] | All 2012 Acquisitions [Member]
Business Acquisition [Line Items]
Intangible assets		$ 16,900