Derivative Financial Instruments - Outstanding Balances (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	$ 2,043	$ 9,293
Fair Value	31	144
Gains/(Losses)	459	(43)
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,797	5,670
Fair Value	24	16
Gains/(Losses)	(332)	(131)
Loan sale commitments \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	354	1,051
Fair Value	10	25
Gains/(Losses)	(15)	(77)
IRLCs \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	755	5,237
Fair Value	22	134
Gains/(Losses)	(112)	(280)
IRLCs \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	15	10
Fair Value	0	0
Gains/(Losses)	0	0
LPCs \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	145	487
Fair Value	1	3
Gains/(Losses)	(2)	(35)
LPCs \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	209	646
Fair Value	1	2
Gains/(Losses)	1	(1)
Forward MBS trades \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,143	3,569
Fair Value	8	7
Gains/(Losses)	569	272
Forward MBS trades \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	681	4,091
Fair Value	9	8
Gains/(Losses)	(56)	(110)
Treasury futures
Derivatives, Fair Value [Line Items]
Fair Value	14	6
Treasury futures \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	0
Fair Value	0
Gains/(Losses)	4
Treasury futures \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	892	923
Gains/(Losses)	$ (277)	(6)
Swap futures \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional		0
Fair Value		0
Gains/(Losses)		$ (14)

Nominal or face amount used to calculate payments on the derivative asset.

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