Derivative Financial Instruments - Derivative Instruments (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Loan sale commitments
Derivatives, Fair Value [Line Items]
Gain/(Loss)	$ 16	$ (4)
Treasury futures
Derivatives, Fair Value [Line Items]
Gain/(Loss)	113	0
Interest Rate Lock Commitments, Assets
Derivatives, Fair Value [Line Items]
Gain/(Loss)	21	0
us-gaap_InterestRateLockCommitmentsMember
Derivatives, Fair Value [Line Items]
Gain/(Loss)	0	0
Loan Purchase Commitments, Assets
Derivatives, Fair Value [Line Items]
Gain/(Loss)	0	0
Loan Purchase Commitments, Liabilities
Derivatives, Fair Value [Line Items]
Gain/(Loss)	(2)	0
Forward Contracts, Assets
Derivatives, Fair Value [Line Items]
Gain/(Loss)	156	74
Forward Contracts, Liabilities
Derivatives, Fair Value [Line Items]
Gain/(Loss)	(237)	(97)
Treasury futures, Liabilities
Derivatives, Fair Value [Line Items]
Gain/(Loss)		(196)
Derivative financial instruments, liabilities
Derivatives, Fair Value [Line Items]
Gain/(Loss)	(239)	(293)
Derivative financial instruments, assets
Derivatives, Fair Value [Line Items]
Gain/(Loss)	290	74
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	8,446	2,322
Fair Value	67	36
Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional	992	304
Fair Value	27	6
Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,464	813
Fair Value	41	22
Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	558	121
Fair Value	3	1
Assets \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	2,152	1,383
Fair Value	7	13
Assets \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	4,272	5
Fair Value	16	0
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	10,253	3,930
Fair Value	(47)	(95)
Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	49	40
Fair Value	0	0
Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	571	288
Fair Value	(3)	(2)
Liabilities \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	9,633	1,249
Fair Value	$ (44)	(28)
Liabilities \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional		2,353
Fair Value		$ (65)

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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- Definition

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

+ References

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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.

+ References

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- Definition

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

+ References

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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

No definition available.

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