Acquisitions Narrative (Details) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended			24 Months Ended					1 Months Ended		12 Months Ended
	Apr. 30, 2011	Dec. 31, 2011 USD ($) years	Dec. 31, 2011 Access [Member] USD ($) years	Dec. 31, 2010 Access [Member] USD ($)	Dec. 31, 2011 Access [Member] USD ($)	Jun. 30, 2011 Access [Member] USD ($)	Jun. 30, 2011 Access [Member] GBP (£)	Apr. 15, 2011 Access [Member] USD ($)	Apr. 15, 2011 Access [Member] GBP (£)	Oct. 22, 2010 DataCash Group plc [Member] USD ($)	Oct. 22, 2010 DataCash Group plc [Member] GBP (£)	Dec. 31, 2011 DataCash Group plc [Member] USD ($) years	Apr. 15, 2011 Maximum [Member] USD ($)	Apr. 15, 2011 Maximum [Member] GBP (£)	Apr. 15, 2011 Minimum [Member] GBP (£)
Business Acquisition [Line Item]
Business Acquisition, Effective Date of Acquisition	2011-04-15									2010-10-22	2010-10-22
Purchase price to acquire Access								$ 481	£ 295	$ 534	£ 334
Potential undiscounted amount under contingent consideration													57	35	0
Contingent consideration						9	6
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		9	9
Finite-Lived Intangible Assets, Useful Life, Minimum Access		1.5	1.5									1
Finite-Lived Intangible Assets, Useful Life, Maximum		10	10									10
Acquisition related expense			2	4	6							7
Business Acquisition, Purchase Price Allocation, Goodwill Amount								$ 354		$ 402