Derivative Financial Instruments - Derivative Instruments (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023
Treasury futures
Derivatives, Fair Value [Line Items]
Fair Value		$ (20)
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	$ 6,574	3,025
Fair Value	102	41
Gain/(Loss)	(26)	51
Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional	652	556
Fair Value	22	8
Gain/(Loss)	11	(1)
Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,029	1,041
Fair Value	31	30
Gain/(Loss)	10	8
Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	324	200
Fair Value	2	1
Gain/(Loss)	(1)	0
Assets \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,789	1,712
Fair Value	7	10
Gain/(Loss)	15	43
Assets \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	3,432	72
Fair Value	62	0
Gain/(Loss)	(50)	0
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	5,772	3,937
Fair Value	(13)	(24)
Gain/(Loss)	(184)	(94)
Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	25	18
Fair Value	0	0
Gain/(Loss)	0	0
Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	480	234
Fair Value		(1)
Gain/(Loss)	(1)	0
Liabilities \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	4,797	1,175
Fair Value	(8)	(3)
Gain/(Loss)	(87)	(50)
Liabilities \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	470	2,510
Fair Value	(3)
Gain/(Loss)	$ (96)	$ (44)

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.

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- Definition

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

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- Definition

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.

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- Definition

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

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- Definition

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

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