Number of shares sold to selected financial institutions.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: 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=25496072&loc=d3e14326-108349

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Guarantees - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	1 Months Ended
	May. 31, 2009	Mar. 31, 2016	Dec. 31, 2015
Business Combination, Contingent Consideration, Liability			$ 23
Standby Letters of Credit
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 3,000	2,900
Mortgage Servicing Rights [Member]
Loss Contingency Accrual, at Carrying Value		$ 12	$ 14
Derivative Financial Instruments, Liabilities [Member] \| Visa Interest [Member]
Number Of Shares Sold To Selected Financial Institutions	3.2
Not Designated as Hedging Instrument [Member] \| Derivative Financial Instruments, Liabilities [Member] \| Visa Interest [Member]
Number Of Shares Sold To Selected Financial Institutions	3.2