Investment Securities - Schedule of Unrealized Loss on Investments (Details) - USD ($)	Jun. 30, 2026	Dec. 31, 2025
Less than 12 months
Fair value	$ 4,455,000,000	$ 580,000,000
Unrealized loss	(35,000,000)	(3,000,000)
12 months or longer
Fair value	15,368,000,000	16,382,000,000
Unrealized loss	(2,960,000,000)	(2,925,000,000)
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	1,921,000,000	0
Unrealized loss	(8,000,000)	0
12 months or longer
Fair value	570,000,000	609,000,000
Unrealized loss	(56,000,000)	(51,000,000)
U.S. States and political subdivisions
Less than 12 months
Fair value	30,000,000	24,000,000
Unrealized loss	0	0
12 months or longer
Fair value	361,000,000	429,000,000
Unrealized loss	(65,000,000)	(74,000,000)
Foreign government
Less than 12 months
Fair value	47,000,000	51,000,000
Unrealized loss	0	(1,000,000)
12 months or longer
Fair value	66,000,000	72,000,000
Unrealized loss	(3,000,000)	(3,000,000)
Agency mortgage-backed residential
Less than 12 months
Fair value	825,000,000	120,000,000
Unrealized loss	(9,000,000)	0
12 months or longer
Fair value	9,674,000,000	10,310,000,000
Unrealized loss	(2,117,000,000)	(2,084,000,000)
Mortgage-backed residential
Less than 12 months
Fair value	0	0
Unrealized loss	0	0
12 months or longer
Fair value	188,000,000	198,000,000
Unrealized loss	(33,000,000)	(32,000,000)
Agency mortgage-backed commercial
Less than 12 months
Fair value	1,207,000,000	299,000,000
Unrealized loss	(12,000,000)	(1,000,000)
12 months or longer
Fair value	3,518,000,000	3,629,000,000
Unrealized loss	(624,000,000)	(621,000,000)
Asset-backed
Less than 12 months
Fair value	0	0
Unrealized loss	0	0
12 months or longer
Fair value	1,000,000	12,000,000
Unrealized loss	0	0
Corporate debt
Less than 12 months
Fair value	425,000,000	86,000,000
Unrealized loss	(6,000,000)	(1,000,000)
12 months or longer
Fair value	990,000,000	1,123,000,000
Unrealized loss	$ (62,000,000)	$ (60,000,000)

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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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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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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