Investment Securities - Gross Unrealized Losses and Fair Values of Investments in Continuous Unrealized Loss Positions (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
AFS securities, Fair Value
Less than 12 months, Fair Value	$ 35,145	$ 4,043
12 months or more, Fair Value	16,338	27,777
Total, Fair Value	51,483	31,820
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	(1,488)	(37)
12 months or more, Unrealized Losses	(4,666)	(4,613)
Total, Unrealized Losses	(6,154)	(4,650)
U.S. Treasury
AFS securities, Fair Value
Less than 12 months, Fair Value	7,905	704
12 months or more, Fair Value	29	432
Total, Fair Value	7,934	1,136
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	(150)	(16)
12 months or more, Unrealized Losses	(7)	(8)
Total, Unrealized Losses	(157)	(24)
GSE
AFS securities, Fair Value
Less than 12 months, Fair Value	214	65
12 months or more, Fair Value	190	228
Total, Fair Value	404	293
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	(11)	(1)
12 months or more, Unrealized Losses	(33)	(24)
Total, Unrealized Losses	(44)	(25)
Agency MBS – residential
AFS securities, Fair Value
Less than 12 months, Fair Value	25,606	2,882
12 months or more, Fair Value	14,237	24,986
Total, Fair Value	39,843	27,868
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	(1,247)	(8)
12 months or more, Unrealized Losses	(3,949)	(4,009)
Total, Unrealized Losses	(5,196)	(4,017)
Debt Securities, Held-to-Maturity, Fair Value
Less than 12 months, Fair Value	3,559	0
12 months or more, Fair Value	34,307	39,130
Total, Fair Value	37,866	39,130
Debt Securities, Held-To-Maturity, Unrealized Losses
Less than 12 months, Unrealized Losses	(85)	0
12 months or more, Fair Value	(10,318)	(8,056)
Total, Fair Value	(10,403)	(8,056)
Agency MBS – commercial
AFS securities, Fair Value
Less than 12 months, Fair Value	1,198	227
12 months or more, Fair Value	1,880	2,093
Total, Fair Value	3,078	2,320
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	(53)	(2)
12 months or more, Unrealized Losses	(677)	(572)
Total, Unrealized Losses	(730)	(574)
States and political subdivisions
AFS securities, Fair Value
Less than 12 months, Fair Value	222	158
12 months or more, Fair Value	0	31
Total, Fair Value	222	189
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	(27)	(10)
12 months or more, Unrealized Losses	0	0
Total, Unrealized Losses	(27)	(10)
Other
AFS securities, Fair Value
Less than 12 months, Fair Value	0	7
12 months or more, Fair Value	2	7
Total, Fair Value	2	14
AFS securities, Unrealized Losses
Less than 12 months, Unrealized Losses	0	0
12 months or more, Unrealized Losses	0	0
Total, Unrealized Losses	$ 0	$ 0

Debt Securities, Available-For-Sale, Unrealized Loss Position, Fair Value

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