Debt Securities (Schedule Of Gross Unrealized Losses And Estimated Fair Value Of Securities Available For Sale) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 957	$ 9,881
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(4)	(256)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	12,433	14,303
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(869)	(1,729)
Debt Securities, Available-for-sale, Unrealized Loss Position	13,390	24,184
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(873)	(1,985)
U.S. Treasury securities
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	203	612
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1)	(14)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,197	1,033
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(46)	(73)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,400	1,645
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(47)	(87)
Federal agency securities
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	155
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	57	195
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(7)	(14)
Debt Securities, Available-for-sale, Unrealized Loss Position	57	350
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(7)	(17)
Residential agency
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	8,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(203)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	8,498	9,605
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(677)	(1,354)
Debt Securities, Available-for-sale, Unrealized Loss Position	8,498	17,617
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(677)	(1,557)
Commercial agency
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	754	1,043
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3)	(35)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,430	2,991
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(127)	(265)
Debt Securities, Available-for-sale, Unrealized Loss Position	3,184	4,034
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(130)	(300)
Commercial non-agency
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	82	82
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(9)	(10)
Debt Securities, Available-for-sale, Unrealized Loss Position	82	82
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(9)	(10)
Corporate and other debt securities
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	59
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	169	397
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(3)	(13)
Debt Securities, Available-for-sale, Unrealized Loss Position	169	456
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (3)	$ (14)

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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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