Mortgage Servicing Rights - Changes in the Fair Value of Residential First Mortgage MSRs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Servicing Asset at Fair Value [Roll Forward]
Balance at beginning of period	$ 1,111
Decrease in MSR fair value due to pay-offs, pay-downs, run-off, model changes, and other (1)	(105)	$ (80)	$ (8)
Changes in estimates of fair value due to interest rate risk	30	1	$ 10
Fair value of MSRs at end of period	$ 26	$ 1,111
Servicing Asset, Fair Value, Change in Fair Value, Other, Statement of Income or Comprehensive Income [Extensible Enumeration]	Mortgage Servicing Rights (MSR) Impairment (Recovery)	Mortgage Servicing Rights (MSR) Impairment (Recovery)	Mortgage Servicing Rights (MSR) Impairment (Recovery)
Residential First Mortgage
Servicing Asset at Fair Value [Roll Forward]
Balance at beginning of period	$ 1,111	$ 1,033	$ 1,012
Additions from loans sold with servicing retained	184	208	19
Reductions from sales	(1,194)	(51)	0
Decrease in MSR fair value due to pay-offs, pay-downs, run-off, model changes, and other (1)	(105)	(80)	(8)
Changes in estimates of fair value due to interest rate risk	30	1	10
Fair value of MSRs at end of period	$ 26	$ 1,111	$ 1,033