Loans - Impaired Loans, Excluding Acquired Loans (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Impaired Financing Receivable:
With an Allowance	$ 2,421		$ 1,822
Without an Allowance	511		642
Total Recorded Investment	2,932		2,464
Related Allowance	457		349
Net Recorded Investment	2,475		2,115
Unpaid Principal Balance	3,400		2,894
Average Recorded Investment	2,698	$ 1,901
Interest Income Recognized	43	40
Credit Card Portfolio Segment [Member]
Impaired Financing Receivable:
With an Allowance	658		666
Without an Allowance	0		0
Total Recorded Investment	658		666
Related Allowance	213		209
Net Recorded Investment	445		457
Unpaid Principal Balance	640		647
Average Recorded Investment	662	683
Interest Income Recognized	17	16
Consumer Portfolio Segment [Member]
Impaired Financing Receivable:
With an Allowance	566		553
Without an Allowance	354		361
Total Recorded Investment	920		914
Related Allowance	51		54
Net Recorded Investment	869		860
Unpaid Principal Balance	1,297		1,290
Average Recorded Investment	917	862
Interest Income Recognized	23	22
Consumer Portfolio Segment [Member] \| Auto
Impaired Financing Receivable:
With an Allowance	283		273
Without an Allowance	211		215
Total Recorded Investment	494		488
Related Allowance	22		22
Net Recorded Investment	472		466
Unpaid Principal Balance	778		772
Average Recorded Investment	491	444
Interest Income Recognized	22	21
Consumer Portfolio Segment [Member] \| Home loan
Impaired Financing Receivable:
With an Allowance	233		229
Without an Allowance	133		136
Total Recorded Investment	366		365
Related Allowance	15		18
Net Recorded Investment	351		347
Unpaid Principal Balance	458		456
Average Recorded Investment	366	366
Interest Income Recognized	1	1
Consumer Portfolio Segment [Member] \| Retail banking
Impaired Financing Receivable:
With an Allowance	50		51
Without an Allowance	10		10
Total Recorded Investment	60		61
Related Allowance	14		14
Net Recorded Investment	46		47
Unpaid Principal Balance	61		62
Average Recorded Investment	60	52
Interest Income Recognized	0	0
Commercial Banking
Impaired Financing Receivable:
With an Allowance	1,197		603
Without an Allowance	157		281
Total Recorded Investment	1,354		884
Related Allowance	193		86
Net Recorded Investment	1,161		798
Unpaid Principal Balance	1,463		957
Average Recorded Investment	1,119	356
Interest Income Recognized	3	2
Commercial Banking \| Total commercial lending
Impaired Financing Receivable:
With an Allowance	1,197		597
Without an Allowance	150		281
Total Recorded Investment	1,347		878
Related Allowance	193		86
Net Recorded Investment	1,154		792
Unpaid Principal Balance	1,455		950
Average Recorded Investment	1,113	346
Interest Income Recognized	3	2
Commercial Banking \| Commercial and multifamily real estate
Impaired Financing Receivable:
With an Allowance	106		82
Without an Allowance	27		3
Total Recorded Investment	133		85
Related Allowance	10		11
Net Recorded Investment	123		74
Unpaid Principal Balance	136		88
Average Recorded Investment	109	133
Interest Income Recognized	1	1
Commercial Banking \| Commercial and industrial
Impaired Financing Receivable:
With an Allowance	1,091		515
Without an Allowance	123		278
Total Recorded Investment	1,214		793
Related Allowance	183		75
Net Recorded Investment	1,031		718
Unpaid Principal Balance	1,319		862
Average Recorded Investment	1,004	213
Interest Income Recognized	2	1
Commercial Banking \| Small-ticket commercial real estate
Impaired Financing Receivable:
With an Allowance	0		6
Without an Allowance	7		0
Total Recorded Investment	7		6
Related Allowance	0		0
Net Recorded Investment	7		6
Unpaid Principal Balance	8		7
Average Recorded Investment	6	10
Interest Income Recognized	0	0
Geographic Distribution, Foreign [Member] \| Credit Card Portfolio Segment [Member]
Impaired Financing Receivable:
With an Allowance	133		125
Without an Allowance	0		0
Total Recorded Investment	133		125
Related Allowance	66		59
Net Recorded Investment	67		66
Unpaid Principal Balance	129		121
Average Recorded Investment	129	141
Interest Income Recognized	3	2
Geographic Distribution, Domestic [Member] \| Credit Card Portfolio Segment [Member]
Impaired Financing Receivable:
With an Allowance	525		541
Without an Allowance	0		0
Total Recorded Investment	525		541
Related Allowance	147		150
Net Recorded Investment	378		391
Unpaid Principal Balance	511		$ 526
Average Recorded Investment	533	542
Interest Income Recognized	$ 14	$ 14

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 14A
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