Debt Securities (Schedule Of Fair Value And Unrealized Losses Of Securities) (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 4,714	$ 1,366
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(53)	(9)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,796	3,371
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(380)	(371)
Debt Securities, Available-for-sale, Unrealized Loss Position	7,510	4,737
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(433)	(380)
U.S. Treasury and agencies
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	197	50
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	745	778
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(41)	(38)
Debt Securities, Available-for-sale, Unrealized Loss Position	942	828
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(42)	(38)
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	219	29
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	138	219
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(16)	(15)
Debt Securities, Available-for-sale, Unrealized Loss Position	357	248
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(17)	(15)
Mortgage-backed securities and collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	4,298	1,287
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(51)	(9)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,913	2,374
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(323)	(318)
Debt Securities, Available-for-sale, Unrealized Loss Position	6,211	3,661
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (374)	$ (327)

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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