Loans - TDR - Subsequent Defaults of Completed TDR Modifications (Detail) $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) Contract	Mar. 31, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	21,301	19,977
Total Loans \| $	$ 85	$ 57
Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	19,407	18,215
Total Loans \| $	$ 38	$ 36
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1,877	1,762
Total Loans \| $	$ 24	$ 21
Consumer Portfolio Segment [Member] \| Auto
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1,852	1,747
Total Loans \| $	$ 21	$ 20
Consumer Portfolio Segment [Member] \| Home loan
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	10	5
Total Loans \| $	$ 1	$ 0
Consumer Portfolio Segment [Member] \| Retail banking
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	15	10
Total Loans \| $	$ 2	$ 1
Commercial Banking
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	17	0
Total Loans \| $	$ 23	$ 0
Commercial Banking \| Total commercial lending
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	17	0
Total Loans \| $	$ 23	$ 0
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	0
Total Loans \| $	$ 0	$ 0
Commercial Banking \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	17	0
Total Loans \| $	$ 23	$ 0
Commercial Banking \| Small-ticket commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	0
Total Loans \| $	$ 0	$ 0
Geographic Distribution, Domestic [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	10,594	9,667
Total Loans \| $	$ 18	$ 16
Geographic Distribution, Foreign [Member] \| Credit Card Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8,813	8,548
Total Loans \| $	$ 20	$ 20

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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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