Loans - TDR - Subsequent Defaults of Completed TDR Modifications (Detail) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($) Contract	Sep. 30, 2014 USD ($) Contract	Sep. 30, 2015 USD ($) Contract	Sep. 30, 2014 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts	21,094	20,698	61,493	64,784
Total Loans \| $	$ 67	$ 59	$ 204	$ 202
Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	18,781	18,991	55,281	60,015
Total Loans \| $	$ 37	$ 40	$ 112	$ 131
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	2,307	1,689	6,203	4,737
Total Loans \| $	$ 28	$ 19	$ 73	$ 61
Consumer Portfolio Segment [Member] \| Auto
Financing Receivable, Modifications [Line Items]
Number of Contracts	2,297	1,674	6,172	4,672
Total Loans \| $	$ 27	$ 18	$ 71	$ 49
Consumer Portfolio Segment [Member] \| Home loan
Financing Receivable, Modifications [Line Items]
Number of Contracts	4	2	11	12
Total Loans \| $	$ 1	$ 1	$ 1	$ 3
Consumer Portfolio Segment [Member] \| Retail banking
Financing Receivable, Modifications [Line Items]
Number of Contracts	6	13	20	53
Total Loans \| $	$ 0	$ 0	$ 1	$ 9
Commercial Banking
Financing Receivable, Modifications [Line Items]
Number of Contracts	6	18	9	32
Total Loans \| $	$ 2	$ 0	$ 19	$ 10
Commercial Banking \| Total commercial lending
Financing Receivable, Modifications [Line Items]
Number of Contracts	3	0	6	6
Total Loans \| $	$ 2	$ 0	$ 19	$ 7
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0	0	4
Total Loans \| $	$ 0	$ 0	$ 0	$ 6
Commercial Banking \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts	3	0	6	2
Total Loans \| $	$ 2	$ 0	$ 19	$ 1
Commercial Banking \| Small-ticket commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts	3	18	3	26
Total Loans \| $	$ 0	$ 0	$ 0	$ 3
Geographic Distribution, Domestic [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	10,487	9,882	29,815	30,502
Total Loans \| $	$ 18	$ 16	$ 50	$ 47
Geographic Distribution, Foreign [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	8,294	9,109	25,466	29,513
Total Loans \| $	$ 19	$ 24	$ 62	$ 84

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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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