Payment Status for the LHFI Portfolio (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017		Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Document Period End Date		Mar. 31, 2017
Accruing Current		$ 140,485		$ 140,130
Accruing 30-89 Days Past Due		1,028		1,035
Accruing 90+ Days Past Due		1,227		1,288
Nonaccruing	[2]	789	[1]	845	[3]
Total	[4]	143,529		143,298
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		68,601		68,776
Accruing 30-89 Days Past Due		31		35
Accruing 90+ Days Past Due		11		12
Nonaccruing		328		390
Total		68,971		69,213
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		5,057		4,988
Accruing 30-89 Days Past Due		2		1
Accruing 90+ Days Past Due		2		0
Nonaccruing		6		7
Total		5,067		4,996
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		5,067		4,996
Commercial Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		4,197		3,998
Accruing 30-89 Days Past Due		0		0
Accruing 90+ Days Past Due		0		0
Nonaccruing		18		17
Total		4,215		4,015
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		77,855		77,762
Accruing 30-89 Days Past Due		33		36
Accruing 90+ Days Past Due		13		12
Nonaccruing		352	[1]	414	[3]
Total		78,253		78,224
Federal National Mortgage Association (FNMA) Insured Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		171		155
Accruing 30-89 Days Past Due		55		55
Accruing 90+ Days Past Due		323		327
Nonaccruing		0		0
Total		549		537
Residential Nonguaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		25,854	[5]	25,869	[6]
Accruing 30-89 Days Past Due		67	[5]	84	[6]
Accruing 90+ Days Past Due		10	[5]	7	[6]
Nonaccruing		179		177
Total	[7],[8]	26,110		26,137
Home Equity Line of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		11,201		11,596
Accruing 30-89 Days Past Due		73		81
Accruing 90+ Days Past Due		0		0
Nonaccruing		237		235
Total	[7]	11,511		11,912
Residential Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		367		389
Accruing 30-89 Days Past Due		1		3
Accruing 90+ Days Past Due		0		0
Nonaccruing		12		12
Total	[7]	380		404
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		37,593		38,009
Accruing 30-89 Days Past Due		196		223
Accruing 90+ Days Past Due		333		334
Nonaccruing		428	[1]	424	[3]
Total		38,550		38,990
Federal Family Education Loan Program (FFELP) Guaranteed Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		4,862		4,637
Accruing 30-89 Days Past Due		667		603
Accruing 90+ Days Past Due		867		927
Nonaccruing		0		0
Total		6,396		6,167
Consumer Other Direct [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		7,865		7,726
Accruing 30-89 Days Past Due		31		35
Accruing 90+ Days Past Due		3		4
Nonaccruing		5		6
Total	[9]	7,904		7,771
Consumer Indirect [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		10,972		10,608
Accruing 30-89 Days Past Due		91		126
Accruing 90+ Days Past Due		0		1
Nonaccruing		4		1
Total	[9]	11,067		10,736
Credit Card Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		1,338		1,388
Accruing 30-89 Days Past Due		10		12
Accruing 90+ Days Past Due		11		10
Nonaccruing		0		0
Total	[9]	1,359		1,410
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Current		25,037		24,359
Accruing 30-89 Days Past Due		799		776
Accruing 90+ Days Past Due		881		942
Nonaccruing		9	[1]	7	[3]
Total		$ 26,726		$ 26,084

[1] Nonaccruing loans past due 90 days or more totaled $348 million. Nonaccruing loans past due fewer than 90 days include modified nonaccrual loans reported as TDRs, performing second lien loans where the first lien loan is nonperforming, and certain energy-related commercial loans.

[2] Nonaccruing restructured loans are included in total nonaccrual/NPLs.

[3] Nonaccruing loans past due 90 days or more totaled $360 million. Nonaccruing loans past due fewer than 90 days include modified nonaccrual loans reported as TDRs and performing second lien loans where the first lien loan is nonperforming, and certain energy-related commercial loans.

[4] Includes loans of consolidated VIEs of $201 million and $211 million at March 31, 2017 and December 31, 2016, respectively.

[5] Includes $221 million of loans measured at fair value, the majority of which were accruing current.

[6] Includes $222 million of loans measured at fair value, the majority of which were accruing current.

[7] Excludes $549 million and $537 million of guaranteed residential loans at March 31, 2017 and December 31, 2016, respectively.

[8] Includes $221 million and $222 million of LHFI measured at fair value at March 31, 2017 and December 31, 2016, respectively.

[9] Excludes $6.4 billion and $6.2 billion of guaranteed student loans at March 31, 2017 and December 31, 2016, respectively.