Derivative Financial Instruments - Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Treasury futures
Derivatives, Fair Value [Line Items]
Fair Value		$ (49)
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	$ 4,925	7,983
Fair Value	125	153
Gains/(Losses)	119	161
Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional	399	543
Fair Value	12	1
Gains/(Losses)	2	(24)
Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	940	3,122
Fair Value	33	72
Gains/(Losses)	11	(62)
Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	484	203
Fair Value	3	2
Gains/(Losses)	2	(1)
Assets \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,056	4,658
Fair Value	18	79
Gains/(Losses)	35	224
Assets \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	2,445
Fair Value	71
Gains/(Losses)	71
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,742	3,001
Fair Value	(11)	(68)
Gains/(Losses)	(69)	(115)
Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	25	551
Fair Value	0	(5)
Gains/(Losses)	0	(5)
Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	85	658
Fair Value	0	(8)
Gains/(Losses)	1	(6)
Liabilities \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,439	695
Fair Value	(10)	(6)
Gains/(Losses)	(47)	7
Liabilities \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	193	1,097
Gains/(Losses)	$ (23)	$ (111)

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

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- Definition

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

+ References

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

+ References

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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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