Investment Securities (Schedule of Unrealized Loss on Investments) (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Less than 12 months
Fair value	$ 500,000,000	$ 590,000,000
Unrealized loss	(10,000,000)	(10,000,000)
12 months or longer
Fair value	22,781,000,000	23,331,000,000
Unrealized loss	(4,424,000,000)	(4,000,000,000)
Credit reserves, available-for-sale	0	0
Credit reserves, held-to-maturity	0	0
U.S. Treasury and federal agencies
Less than 12 months
Fair value	0	0
Unrealized loss	0	0
12 months or longer
Fair value	2,057,000,000	2,075,000,000
Unrealized loss	(229,000,000)	(209,000,000)
U.S. States and political subdivisions
Less than 12 months
Fair value	112,000,000	70,000,000
Unrealized loss	(1,000,000)	0
12 months or longer
Fair value	488,000,000	501,000,000
Unrealized loss	(76,000,000)	(70,000,000)
Foreign government
Less than 12 months
Fair value	27,000,000	16,000,000
Unrealized loss	(1,000,000)	0
12 months or longer
Fair value	130,000,000	134,000,000
Unrealized loss	(9,000,000)	(8,000,000)
Agency mortgage-backed residential
Less than 12 months
Fair value	123,000,000	300,000,000
Unrealized loss	(2,000,000)	(5,000,000)
12 months or longer
Fair value	14,606,000,000	15,015,000,000
Unrealized loss	(3,077,000,000)	(2,734,000,000)
Mortgage-backed residential
Less than 12 months
Fair value	0	0
Unrealized loss	0	0
12 months or longer
Fair value	219,000,000	225,000,000
Unrealized loss	(45,000,000)	(43,000,000)
Agency mortgage-backed commercial
Less than 12 months
Fair value	167,000,000	153,000,000
Unrealized loss	(5,000,000)	(4,000,000)
12 months or longer
Fair value	3,448,000,000	3,472,000,000
Unrealized loss	(830,000,000)	(779,000,000)
Asset-backed
Less than 12 months
Fair value	18,000,000	18,000,000
Unrealized loss	0	0
12 months or longer
Fair value	275,000,000	302,000,000
Unrealized loss	(9,000,000)	(12,000,000)
Corporate debt
Less than 12 months
Fair value	53,000,000	33,000,000
Unrealized loss	(1,000,000)	(1,000,000)
12 months or longer
Fair value	1,558,000,000	1,607,000,000
Unrealized loss	$ (149,000,000)	$ (145,000,000)

Debt Securities, Available-for-Sale, Unrealized Loss Position, Long

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Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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