Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Computer hardware and software	100,383	$ 78,460
Card-reading equipment	13,066	12,649
Furniture, fixtures, and vehicles	10,319	9,420
Buildings and improvements	11,294	10,571
Property, plant and equipment, gross	135,062	111,100
Less: accumulated depreciation	(61,499)	(57,144)
Property, plant and equipment, net	73,563	$ 53,956
Minimum [Member] | Computer Hardware and Software [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	3 years
Minimum [Member] | Furniture Fixtures and Vehicles [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	3 years
Minimum [Member] | Building and Improvements [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	10 years
Maximum [Member] | Computer Hardware and Software [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	7 years
Maximum [Member] | Card-Reading Equipment [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	5 years
Maximum [Member] | Furniture Fixtures and Vehicles [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	6 years
Maximum [Member] | Building and Improvements [Member]
Depreciation and Amortization Expenses For Property Plant And Equipment [Line Items]
Estimated Useful Lives	30 years