Commitments and Contingencies Disclosure [Line Items]

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- Definition

Debt Instruments, Redemption Price

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- Definition

Litigation Reserve Remaining Reserves

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- Definition

Loss Contingency, Claims Dismissed, Number

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- Definition

Loss Contingency Class Action Lawsuits Filed

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Number of Cases that were Consolidated

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Payment To Compensate Parties Harmed By Market Timing Activities

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Accruals related to the obligation to share in potential losses resulting from certain indemnified litigation relating to an equity investee.

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- Definition

The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10, 11, 12
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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The total number of new claims filed pertaining to a loss contingency during the period.

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Legal and Regulatory Proceedings - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended						3 Months Ended
	Dec. 31, 2008 LegalMatter	Dec. 31, 2010 Visa Litigation	Dec. 31, 2007 Visa Litigation	Jun. 30, 2011 Visa Litigation	Jun. 30, 2010 Visa Litigation	Dec. 31, 2009 Visa Litigation	Jun. 30, 2011 Upper Limit Trust Preferred Securities	Jun. 30, 2011 Trust Preferred Securities
Commitments and Contingencies Disclosure [Line Items]
Remaining litigation reserve						$ 243
Share of the Visa escrow account		199	169
Reserves for litigation		30	3	31	26
Number of putative securities class action complaints	5
Number of cases that have been consolidated	5
Number of additional lawsuit filed	2
Number of alleging violations of ERISA that were dismissed	2
Aggregate cash redemption price								$ 25.18
Total amount of compensation payments							$ 1.5