Derivative Financial Instruments - Derivative Instruments (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Treasury futures
Derivatives, Fair Value [Line Items]
Fair Value	$ (62)
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	3,467	$ 19,824
Fair Value	96	234
Gains/(Losses)	431	(39)
Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional	439	1,435
Fair Value		29
Fair Value	(3)
Gains/(Losses)	(28)	(73)
Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,118	6,167
Fair Value	21	167
Gains/(Losses)	(113)	(247)
Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	53	887
Fair Value	1	6
Gains/(Losses)	(2)	(33)
Assets \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	2,296	12,770
Fair Value	74	61
Gains/(Losses)	542	240
Assets \| Swap futures
Derivatives, Fair Value [Line Items]
Outstanding Notional		0
Fair Value		0
Gains/(Losses)		1
Assets \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	0
Fair Value	0
Gains/(Losses)	4
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	2,038	9,486
Fair Value	(94)	(48)
Gains/(Losses)	(344)	(152)
Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	551	25
Fair Value	(8)	0
Gains/(Losses)	(8)	0
Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	223	2,208
Fair Value	(5)	(13)
Gains/(Losses)	(2)	(12)
Liabilities \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	458	6,553
Fair Value	(19)	(23)
Gains/(Losses)	(72)	(122)
Liabilities \| Swap futures
Derivatives, Fair Value [Line Items]
Outstanding Notional		700
Fair Value		(12)
Gains/(Losses)		$ (18)
Liabilities \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	806
Gains/(Losses)	$ (262)

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.

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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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