Fair Value, Assets and Liabilities, Changes in Level 3 Fair Value Assets and Liabilities on a Recurring Basis (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Trading debt securities [Member]
Assets:
Balance, beginning of period	$ 157	$ 185
Net gains (losses)	0	1
Purchases	46	76
Sales	(79)	(112)
Settlements	(2)	(1)
Transfers into Level 3	14	0
Transfers out of Level 3	(13)	(17)
Balance, end of period	123	132
Net unrealized gain (losses), related to assets and liabilities held at period end	1	1
Available-for-sale debt securities [Member]
Assets:
Balance, beginning of period	221	276
Net gains (losses)	(2)	(20)
Purchases	5	69
Sales	0	0
Settlements	(3)	(6)
Transfers into Level 3	0	233
Transfers out of Level 3	(28)	(47)
Balance, end of period	193	505
Net unrealized gain (losses), related to assets and liabilities held at period end	(2)	(19)
Fair Value Disclosures, Textual [Abstract]
Total net gains (losses) related to assets held at period end and included in other comprehensive income	0	(16)
Total unrealized net gains (losses) related to assets held at period end and included in other comprehensive income	0	(15)
Loans held for sale [Member]
Assets:
Balance, beginning of period	448	793
Net gains (losses)	(2)	10
Purchases	71	73
Sales	(19)	(49)
Settlements	(47)	(39)
Transfers into Level 3	34	16
Transfers out of Level 3	(163)	(240)
Balance, end of period	322	564
Net unrealized gain (losses), related to assets and liabilities held at period end	(2)	10
Mortgage servicing rights [Member] | Total Consumer [Member] | Residential mortgage [Member]
Assets:
Balance, beginning of period	7,468	9,310
Net gains (losses)	25	(546)
Purchases	19	48
Sales	(263)	7
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, end of period	7,249	8,819
Net unrealized gain (losses), related to assets and liabilities held at period end	251	(225)
Derivative [Member]
Net Derivative Assets (Liabilities):
Balance, beginning of period	(4,998)	(3,797)
Net gains (losses)	(2,110)	(63)
Purchases	0	2
Sales	(1)	(1)
Settlements	796	589
Transfers into Level 3	(45)	(786)
Transfers out of Level 3	28	16
Balance, end of period	(6,330)	(4,040)
Net unrealized gains (losses) related to assets and liabilities held at period end	(1,387)	466
Derivative [Member] | Interest rate contracts [Member]
Net Derivative Assets (Liabilities):
Balance, beginning of period	(3,567)	(2,582)
Net gains (losses)	(1,872)	295
Purchases	0	0
Sales	0	0
Settlements	714	267
Transfers into Level 3	0	(746)
Transfers out of Level 3	0	14
Balance, end of period	(4,725)	(2,752)
Net unrealized gains (losses) related to assets and liabilities held at period end	(1,199)	509
Derivative [Member] | Equity contracts [Member]
Net Derivative Assets (Liabilities):
Balance, beginning of period	(1,474)	(1,224)
Net gains (losses)	(263)	(303)
Purchases	0	0
Sales	0	0
Settlements	155	285
Transfers into Level 3	(45)	(38)
Transfers out of Level 3	28	2
Balance, end of period	(1,599)	(1,278)
Net unrealized gains (losses) related to assets and liabilities held at period end	(128)	(2)
Derivative [Member] | Other derivative contracts [Member]
Net Derivative Assets (Liabilities):
Balance, beginning of period	43	9
Net gains (losses)	25	(55)
Purchases	0	2
Sales	(1)	(1)
Settlements	(73)	37
Transfers into Level 3	0	(2)
Transfers out of Level 3	0	0
Balance, end of period	(6)	(10)
Net unrealized gains (losses) related to assets and liabilities held at period end	(60)	(41)
Securities [Member] | Equity securities [Member]
Assets:
Balance, beginning of period	43	20
Net gains (losses)	3	(1)
Purchases	8	0
Sales	(5)	0
Settlements	0	0
Transfers into Level 3	0	13
Transfers out of Level 3	0	0
Balance, end of period	49	32
Net unrealized gain (losses), related to assets and liabilities held at period end	3	(1)
Other assets and liabilities [Member]
Assets and Liabilities:
Balance, beginning of period	(34)	(167)
Net gains (losses)	142	(26)
Purchases	0	0
Sales	(1)	0
Settlements	0	0
Transfers into level 3	0	0
Transfers out of Level 3	0	0
Balance, end of period	107	(193)
Net unrealized gain (losses), related to assets and liabilities held at period end	142	(26)
Fair Value Disclosures, Textual [Abstract]
Total net gains (losses) related to other assets and liabilities held at period end and included in other comprehensive income	(2)	0
Total unrealized net gains (losses) related to assets and liabilities held at period end and included in other comprehensive income	$ (2)	$ 0