Fair Value Measurements - Reconciliation of Level 3 (Details) - Recurring Fair Value Measurements - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Excess spread financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	$ 437	$ 509
Changes in fair value included in earnings	15	8
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(1)	0	0
Repayments	(2)	(9)
Settlements	(64)	(71)
Other changes	0	0
Balance - end of year	386	437
Mortgage servicing rights financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	29	19
Changes in fair value included in earnings	3	10
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(1)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of year	32	29
LPCs
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - end of year	7
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	9,090	6,654
Changes in fair value included in earnings	(273)	(483)
Purchases/additions(1)	3,004	3,189
Issuances	460	273
Sales/dispositions(1)	(583)	(573)
Repayments	0	0
Settlements	0	0
Other changes	38	(30)
Balance - end of year	11,736	9,090
Mortgage loans held for sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	81	74
Changes in fair value included in earnings	5	18
Purchases/additions(1)	130	180
Issuances	0	0
Sales/dispositions(1)	(153)	(189)
Repayments	(2)	(6)
Settlements	0	0
Other changes	(1)	4
Balance - end of year	60	81
Equity investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	8	45
Changes in fair value included in earnings	0	(37)
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(1)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of year	8	8
IRLCs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of year	21	22
Changes in fair value included in earnings	1	(1)
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(1)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of year	$ 22	$ 21