Guarantees, Pledged Assets and Collateral (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		$ (244)		$ (244)		$ 136
Maximum exposure to loss, expires in one year or less		30,319		30,319		27,689
Maximum exposure to loss, expires in one year through three years		19,675		19,675		20,190
Maximum exposure to loss, expires in three years through five years		8,645		8,645		8,732
Maximum exposure to loss, expires after five years		15,622		15,622		15,212
Maximum exposure to loss		74,261		74,261		71,823
Total assets	[1]	1,930,871		1,930,871		1,930,115
Securities owned and pledged as collateral related to repurchase agreements not available to be repledged, Fair Value		4,700		4,700		6,600
Mortgages held for sale		4,500		4,500		15,800
Carrying value of delinquent loans eligible for repurchase		1,100		1,100		1,200
Security Owned and Pledged as Collateral, Fair Value [Abstract]
Trading assets and other		107,374		107,374		84,603
Investment securities		75,174		75,174		90,946
Mortgages held for sale and loans		496,164		496,164		516,112
Total pledged assets		678,712		678,712		691,661
Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		35,128		35,128		34,167
Written put options [Member]
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		(334)		(334)		37
Maximum exposure to loss, expires in one year or less		14,781		14,781		10,427
Maximum exposure to loss, expires in one year through three years		10,702		10,702		10,805
Maximum exposure to loss, expires in three years through five years		4,263		4,263		4,573
Maximum exposure to loss, expires after five years		1,244		1,244		1,216
Maximum exposure to loss		30,990		30,990		27,021
Written put options [Member] | Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		17,899		17,899		15,915
Direct pay letters of credit (DPLCs) [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		9,100		9,100		9,200
Third Party Clearing Indemnifications [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		600		600		1,200
Third-party Clearing Customer Obligations		67		67		175
Collateral Provided to Third-party Clearing Agents		533		533		991
Standby Letters of Credit [Member]
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		38		38		38
Maximum exposure to loss, expires in one year or less		14,725		14,725		16,050
Maximum exposure to loss, expires in one year through three years		8,420		8,420		8,727
Maximum exposure to loss, expires in three years through five years		3,451		3,451		3,194
Maximum exposure to loss, expires after five years		685		685		658
Maximum exposure to loss		27,281		27,281		28,629
Standby Letters of Credit [Member] | Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		8,915		8,915		9,898
Securities lending and other indemnifications [Member]
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		0		0		0
Maximum exposure to loss, expires in one year or less		1		1		0
Maximum exposure to loss, expires in one year through three years		0		0		0
Maximum exposure to loss, expires in three years through five years		1		1		1
Maximum exposure to loss, expires after five years		600		600		1,166
Maximum exposure to loss		602		602		1,167
Securities lending and other indemnifications [Member] | Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		2		2		2
Loans and MHFS sold with recourse [Member]
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		51		51		55
Maximum exposure to loss, expires in one year or less		191		191		84
Maximum exposure to loss, expires in one year through three years		547		547		637
Maximum exposure to loss, expires in three years through five years		928		928		947
Maximum exposure to loss, expires after five years		8,865		8,865		8,592
Maximum exposure to loss		10,531		10,531		10,260
Loans and MHFS sold with recourse [Member] | Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		7,751		7,751		7,228
Factoring guarantee [Member]
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		0		0		0
Maximum exposure to loss, expires in one year or less		621		621		1,109
Maximum exposure to loss, expires in one year through three years		0		0		0
Maximum exposure to loss, expires in three years through five years		0		0		0
Maximum exposure to loss, expires after five years		0		0		0
Maximum exposure to loss		621		621		1,109
Factoring guarantee [Member] | Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		557		557		1,109
Other guarantees [Member]
Guarantor Obligations [Line Items]
Carrying value of obligation (asset)		1		1		6
Maximum exposure to loss, expires in one year or less		0		0		19
Maximum exposure to loss, expires in one year through three years		6		6		21
Maximum exposure to loss, expires in three years through five years		2		2		17
Maximum exposure to loss, expires after five years		4,228		4,228		3,580
Maximum exposure to loss		4,236		4,236		3,637
Other guarantees [Member] | Non-investment grade [Member]
Guarantor Obligations [Line Items]
Maximum exposure to loss		4		4		15
Loans and MHFS sold with recourse [Member]
Guarantor Obligations [Line Items]
Loans repurchased		1	$ 1	2	$ 2
Trading assets and other [Member]
Guarantor Obligations [Line Items]
Securities owned and pledged as collateral available to be repledged, Fair Value		107,300		107,300		84,200
Security Owned and Pledged as Collateral, Fair Value [Abstract]
Trading assets and other		36,400		36,400		33,200
Other Trading - Off-Balance Sheet [Member]
Security Owned and Pledged as Collateral, Fair Value [Abstract]
Trading assets and other		71,000		71,000		51,400
Investment securities [Member]
Guarantor Obligations [Line Items]
Securities owned and pledged as collateral available to be repledged, Fair Value		87		87		617
Securities owned and pledged as collateral related to repurchase agreements not available to be repledged, carrying value		4,600		4,600		6,200
Securities owned and pledged as collateral related to repurchase agreements not available to be repledged, Fair Value		4,600		4,600		6,200
Consolidated VIEs [Member]
Guarantor Obligations [Line Items]
Total assets		13,021		13,021		13,414
Secured Borrowing transactions excluded [Member]
Guarantor Obligations [Line Items]
Total assets		$ 709		$ 709		$ 1,136

[1] Our consolidated assets at June 30, 2017, and December 31, 2016, include the following assets of certain variable interest entities (VIEs) that can only be used to settle the liabilities of those VIEs: Cash and due from banks, $112 million and $168 million; Federal funds sold, securities purchased under resale agreements and other short-term investments, $424 million and $74 million; Trading assets, $50 million and $130 million; Investment securities, $0 million at both period ends; Net loans, $12.1 billion and $12.6 billion; Derivative assets, $0 million and $1 million; Other assets, $339 million and $452 million; and Total assets, $13.0 billion and $13.4 billion, respectively.