Legal and Regulatory Proceedings (Details)	12 Months Ended				1 Months Ended			1 Months Ended		3 Months Ended		6 Months Ended					3 Months Ended			1 Months Ended		1 Months Ended		3 Months Ended
	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	Dec. 31, 2011 Australian Payments Systems Act of 1998 [Member]	Feb. 07, 2011 Event Involving Visa Parties, Member Banks and MasterCard [Member]	Feb. 07, 2011 Event Involving Member Banks and MasterCard [Member]	Nov. 30, 2009 Other State Court Currency Conversion Action [Member] USD ($)	Jul. 31, 2006 MDL Action [Member] USD ($)	Jul. 31, 2006 Schwartz Matter [Member] USD ($)	Dec. 31, 2009 Hungarian Competition Authority [Member] USD ($)	Mar. 31, 2008 Cross Border [Member] USD ($)	Jun. 30, 2008 Cross Border [Member]	Nov. 03, 2010 Italian Competition Authority [Member] USD ($)	Nov. 03, 2010 Italian Competition Authority [Member] EUR (€)	Dec. 31, 2011 Canadian Competition Bureau [Member] USD ($)	Sep. 30, 2009 State Unfair Competition [Member] USD ($)	Dec. 31, 2011 American Express Settlement [Member] USD ($)	Sep. 30, 2008 American Express Settlement [Member] USD ($)	Jun. 30, 2008 American Express Settlement [Member] USD ($) numberofpayments	Nov. 30, 2008 Discover Lawsuit [Member] USD ($)	Oct. 31, 2008 Discover Lawsuit [Member] USD ($)	Mar. 31, 2009 Undertakings to European Commission [Member]	Mar. 31, 2009 Undertakings to European Commission [Member] Credit Card Transactions [Member]	Sep. 30, 2008 Maximum [Member] American Express Settlement [Member] USD ($)	Dec. 31, 2011 Scenario, Forecast [Member] USD ($)
Legal And Regulatory [Line Items]
Obligation Under the terms of Settlement, Number of Payments.																			12
Litigation settlement payments, American Express																	$ 150,000,000	$ 150,000,000						$ 150,000,000
Amount of settlement																					2,800,000,000
Compensatory damages sought, Canadian Competition Bureau															5,000,000,000
Percent of settlement MasterCard would pay					12.00%	36.00%
Provision for litigation settlement	770,000,000	0	0																						770,000,000
Estimated Charge For Financial Portion Of Potential Claims Settlement After Tax																									495,000,000
Daily penalty upon failure to comply European Commission's decision, percentage												3.50%
Daily penalty upon failure to comply European Commission's decision											500,000
Weighted Average Interchange Fee Transaction Basis Point				0.50%																		0.20%	0.30%
Payments for Legal Settlements	303,000,000	607,000,000	946,000,000					72,000,000	13,000,000	3,000,000										863,000,000
Proceeds from litigation settlement																				35,000,000
Accrued litigation payment							4,000,000									6,000,000		1,800,000,000	1,800,000,000
Amount of fine													$ 4,000,000	€ 2,700,000