Fair Value Measurements - Level 3 Reconciliation (Details) - Recurring Fair Value Measurements - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Excess spread financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	$ 386	$ 437
Changes in fair value included in earnings	1	2
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(2)	0	0
Repayments	0	0
Settlements	(30)	(33)
Other changes	0	0
Balance - end of period	357	406
Mortgage servicing rights financing
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	33	29
Changes in fair value included in earnings	(9)	4
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(2)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of period	24	33
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	11,736	9,090
Changes in fair value included in earnings	(728)	(61)
Purchases/additions(1)	289	1,403
Issuances	365	137
Sales/dispositions(2)	(250)	(237)
Repayments	0	0
Settlements	0	0
Other changes	(19)	(20)
Balance - end of period	11,431	10,352
Mortgage loans held for sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	60	81
Changes in fair value included in earnings	2	(1)
Purchases/additions(1)	88	66
Issuances	0	0
Sales/dispositions(2)	(86)	(51)
Repayments	0	(2)
Settlements	0	0
Other changes	0	3
Balance - end of period	64	90
Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period		8
Changes in fair value included in earnings		0
Purchases/additions(1)		0
Issuances		0
Sales/dispositions(2)		0
Repayments		0
Settlements		0
Other changes		0
Balance - end of period		8
Interest Rate Lock Commitments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	22	21
Changes in fair value included in earnings	19	10
Purchases/additions(1)	0	0
Issuances	0	0
Sales/dispositions(2)	0	0
Repayments	0	0
Settlements	0	0
Other changes	0	0
Balance - end of period	41	$ 31
Loan Purchase Commitments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance - beginning of period	6
Changes in fair value included in earnings	6
Purchases/additions(1)	0
Issuances	0
Sales/dispositions(2)	0
Repayments	0
Settlements	0
Other changes	0
Balance - end of period	$ 12