Schedule of Quarterly Financial Data (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Quarterly Financial Information [Line Items]
Total revenue	$ 1,316		$ 1,263		$ 1,253		$ 1,234		$ 1,263		$ 1,201		$ 1,198		$ 1,152		$ 5,066		$ 4,814		$ 4,436
Cost of processing and services	554		537		532		541		516		520		523		522		2,164		2,081		1,936
Cost of product	198		168		171		180		184		164		157		190		717		695		628
Selling, general and administrative expenses	247		243		243		242		266		237		245		229		975		977		824
Total expenses	999		948		946		963		966		921		925		941		3,856		3,753		3,388
Operating income	317		315		307		271		297		280		273		211		1,210		1,061		1,048
Income from continuing operations	181		239		166		168		220		161		152		117		754		650		592
Net income	181		239		166		168		221		159		151		117		754		648		611
Comprehensive income	$ 175		$ 231		$ 171		$ 174		$ 224		$ 163		$ 146		$ 115		$ 751		$ 648		$ 629
Net income per share - continuing operations basic	$ 0.75	[1]	$ 0.96	[1]	$ 0.66	[1]	$ 0.66	[1]	$ 0.85	[1]	$ 0.62	[1]	$ 0.57	[1]	$ 0.44	[1]	$ 3.04	[1]	$ 2.48	[1]	$ 2.18
Net income per share - continuing operations diluted	$ 0.73	[1]	$ 0.95	[1]	$ 0.65	[1]	$ 0.65	[1]	$ 0.84	[1]	$ 0.61	[1]	$ 0.57	[1]	$ 0.43	[1]	$ 2.99	[1]	$ 2.44	[1]	$ 2.15

[1] Net income per share in each period is calculated using actual, unrounded amounts.