Loans - TDR - Subsequent Defaults of Completed TDR Modifications (Detail) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	91,597	85,393	85,799
Total Loans \| $	$ 550	$ 274	$ 271
Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	82,748	76,696	79,009
Total Loans \| $	$ 155	$ 152	$ 169
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8,691	8,687	6,750
Total Loans \| $	$ 112	$ 103	$ 87
Consumer Portfolio Segment [Member] \| Auto
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8,587	8,647	6,651
Total Loans \| $	$ 96	$ 99	$ 72
Consumer Portfolio Segment [Member] \| Home loan
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	56	14	24
Total Loans \| $	$ 7	$ 2	$ 5
Consumer Portfolio Segment [Member] \| Retail banking
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	48	26	75
Total Loans \| $	$ 9	$ 2	$ 10
Commercial Banking
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	158	10	40
Total Loans \| $	$ 283	$ 19	$ 15
Commercial Banking \| Total commercial lending
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	151	7	7
Total Loans \| $	$ 282	$ 19	$ 12
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1	0	5
Total Loans \| $	$ 1	$ 0	$ 11
Commercial Banking \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	150	7	2
Total Loans \| $	$ 281	$ 19	$ 1
Commercial Banking \| Small-ticket commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	7	3	33
Total Loans \| $	$ 1	$ 0	$ 3
Geographic Distribution, Domestic [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	42,250	42,808	40,814
Total Loans \| $	$ 73	$ 71	$ 63
Geographic Distribution, Foreign [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	40,498	33,888	38,195
Total Loans \| $	$ 82	$ 81	$ 106

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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=66008989&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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