Derivative Financial Instruments - Outstanding Balances (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	$ 5,944	$ 2,043
Gains/(Losses)	269	459
Fair Value	159	31
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,171	1,797
Gains/(Losses)	(321)	(332)
Fair Value	9	24
Loan sale commitments \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	337	354
Gains/(Losses)	1	(15)
Fair Value	11	10
IRLCs \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	584	755
Gains/(Losses)	(1)	(112)
Fair Value	21	22
IRLCs \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	1	15
Gains/(Losses)	0	0
Fair Value	0	0
LPCs \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	361	145
Gains/(Losses)	2	(2)
Fair Value	3	1
LPCs \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	41	209
Gains/(Losses)	1	1
Fair Value	0	1
Forward Contracts [Member] \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	2,365	1,143
Gains/(Losses)	155	569
Fair Value	22	8
Forward Contracts [Member] \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,049	681
Gains/(Losses)	(126)	(56)
Fair Value	9	9
Treasury futures
Derivatives, Fair Value [Line Items]
Fair Value		14
Treasury futures \| Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	2,634	0
Gains/(Losses)	113	4
Fair Value	113	0
Treasury futures \| Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	80	892
Gains/(Losses)	(196)	$ (277)
Fair Value	$ 0

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

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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.

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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.

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