Loans and Related Allowance for Credit Losses, Allowance for Credit Losses for Loans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	$ 12,884	$ 16,391	$ 13,788	$ 19,713
Provision for credit losses	773	(1,387)	576	(3,743)
Interest income on certain loans	(26)	(35)	(82)	(112)
Loan charge-offs, total	(736)	(654)	(2,037)	(2,285)
Loan recoveries, total	337	395	989	1,132
Net loan charge-offs	(399)	(259)	(1,048)	(1,153)
Other	(7)	(5)	(9)	0
Allowance for credit losses, ending balance	13,225	14,705	13,225	14,705
Allowance for loan losses	12,571	13,517	12,571	13,517	$ 12,490
Allowance for unfunded credit commitments	$ 654	$ 1,188	$ 654	$ 1,188
Net loan charge-offs (annualized) as a percentage of average total loans	0.17%	0.12%	0.15%	0.18%
Allowance for loan losses as a percentage of total loans	1.33%	1.57%	1.33%	1.57%
Allowance for credit losses for loans as a percentage of total loans	1.40%	1.70%	1.40%	1.70%
Accounts, Notes, Loans and Financing Receivable Textual [Abstract]
Allowance for credit loss for loans, period increase (decrease)			$ (563)
Total Commercial [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	$ 7,082	$ 9,570	7,791	$ 11,516
Provision for credit losses	(72)	(949)	(769)	(2,637)
Interest income on certain loans	(6)	(13)	(22)	(47)
Loan charge-offs, total	(99)	(157)	(235)	(559)
Loan recoveries, total	93	119	235	292
Net loan charge-offs	(6)	(38)	0	(267)
Other	(7)	(5)	(9)	0
Allowance for credit losses, ending balance	6,991	8,565	6,991	8,565
Commercial and industrial loans [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(85)	(144)	(209)	(452)
Loan recoveries, loans	72	98	192	237
Real estate mortgage [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(3)	(5)	(6)	(68)
Loan recoveries, loans	15	15	27	37
Real estate construction [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	0	(1)	0	(1)
Loan recoveries, loans	0	0	0	1
Lease financing [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, lease financing	(11)	(7)	(20)	(38)
Loan recoveries, lease financing	6	6	16	17
Total Consumer [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	5,802	6,821	5,997	8,197
Provision for credit losses	845	(438)	1,345	(1,106)
Interest income on certain loans	(20)	(22)	(60)	(65)
Loan charge-offs, loans	(637)	(497)	(1,802)	(1,726)
Loan recoveries, loans	244	276	754	840
Net loan charge-offs	(393)	(221)	(1,048)	(886)
Other	0	0	0	0
Allowance for credit losses, ending balance	6,234	6,140	6,234	6,140
Residential mortgage - first lien [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(27)	(10)	(78)	(33)
Loan recoveries, loans	28	24	85	90
Residential mortgage - junior lien [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(16)	(15)	(58)	(46)
Loan recoveries, loans	29	43	102	124
Credit card [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(290)	(258)	(844)	(950)
Loan recoveries, loans	88	100	267	300
Auto [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(199)	(107)	(515)	(364)
Loan recoveries, loans	78	81	230	241
Other consumer [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loan charge-offs, loans	(105)	(107)	(307)	(333)
Loan recoveries, loans	$ 21	$ 28	$ 70	$ 85