Loans - TDR - Subsequent Defaults of Completed TDR Modifications (Detail) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract	Dec. 31, 2013 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	85,393	85,799	99,273
Total Loans \| $	$ 274	$ 271	$ 333
Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	76,696	79,009	89,547
Total Loans \| $	$ 152	$ 169	$ 210
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8,687	6,750	9,684
Total Loans \| $	$ 103	$ 87	$ 78
Consumer Portfolio Segment [Member] \| Auto
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8,647	6,651	9,525
Total Loans \| $	$ 99	$ 72	$ 68
Consumer Portfolio Segment [Member] \| Home loan
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	14	24	33
Total Loans \| $	$ 2	$ 5	$ 3
Consumer Portfolio Segment [Member] \| Retail banking
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	26	75	126
Total Loans \| $	$ 2	$ 10	$ 7
Commercial Banking
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	10	40	42
Total Loans \| $	$ 19	$ 15	$ 45
Commercial Banking \| Total commercial lending
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	7	7	38
Total Loans \| $	$ 19	$ 12	$ 45
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	5	14
Total Loans \| $	$ 0	$ 11	$ 23
Commercial Banking \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	7	2	24
Total Loans \| $	$ 19	$ 1	$ 22
Commercial Banking \| Small-ticket commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	3	33	4
Total Loans \| $	$ 0	$ 3	$ 0
Geographic Distribution, Domestic [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	42,808	40,814	41,859
Total Loans \| $	$ 71	$ 63	$ 72
Geographic Distribution, Foreign [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	33,888	38,195	47,688
Total Loans \| $	$ 81	$ 106	$ 138

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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