Debt Securities (Schedule Of Gross Unrealized Losses And Estimated Fair Value Of Securities Available For Sale) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 5,490	$ 957
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(45)	(4)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	10,919	12,433
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(877)	(869)
Debt Securities, Available-for-sale, Unrealized Loss Position	16,409	13,390
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(922)	(873)
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	701	203
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(5)	(1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,064	1,197
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(44)	(46)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,765	1,400
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(49)	(47)
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	251	0
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	54	57
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(7)	(7)
Debt Securities, Available-for-sale, Unrealized Loss Position	305	57
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(8)	(7)
Residential agency
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,773	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(18)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	7,335	8,498
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(684)	(677)
Debt Securities, Available-for-sale, Unrealized Loss Position	9,108	8,498
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(702)	(677)
Commercial agency
Unrealized Loss And Fair Value On Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	2,626	754
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(19)	(3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,267	2,430
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(132)	(127)
Debt Securities, Available-for-sale, Unrealized Loss Position	4,893	3,184
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(151)	(130)
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	(8)	(9)
Debt Securities, Available-for-sale, Unrealized Loss Position	82	82
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(8)	(9)
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	139	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	117	169
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(2)	(3)
Debt Securities, Available-for-sale, Unrealized Loss Position	256	169
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (4)	$ (3)

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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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