Investment Securities - Available-For-Sale Securities in a Gross Unrealized Loss Position (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Available-for-Sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 Months Fair Value	$ 221	$ 481
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(6)
12 Months or Greater Fair Value	1,735	2,229
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(58)	(108)
Agency
Available-for-Sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 Months Fair Value	178	448
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(6)
12 Months or Greater Fair Value	1,713	2,198
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(40)	(95)
Other mortgage-related securities [Member]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Less than 12 Months Fair Value	43	33
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
12 Months or Greater Fair Value	22	31
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (18)	$ (13)