Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Computer hardware and software	$ 244,655	$ 197,958
Card reading equipment	25,462	25,553
Furniture fixtures and Vehicles	18,846	15,418
Buildings and improvements	21,603	14,432
Property, plant and equipment, gross	310,566	253,361
Less: accumulated depreciation	(130,509)	(110,857)
Property, plant and equipment, net	$ 180,057	$ 142,504
Minimum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	3 years
Minimum | Card-reading equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	4 years
Minimum | Furniture, fixtures, and vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	2 years
Minimum | Buildings and improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	5 years
Maximum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	5 years
Maximum | Card-reading equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	6 years
Maximum | Furniture, fixtures, and vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	10 years
Maximum | Buildings and improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (in Years)	50 years