Derivative Financial Instruments - Derivative Instruments (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Assets
Derivatives, Fair Value [Line Items]
Outstanding Notional	$ 18,523	$ 12,295
Fair Value	241	391
Gains/(Losses)	(248)	238
Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,514	1,673
Fair Value	39	81
Gains/(Losses)	(63)	48
Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	6,730	9,227
Fair Value	204	370
Gains/(Losses)	(210)	235
Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	1,984	1,823
Fair Value	10	18
Gains/(Losses)	(28)	6
Assets \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	9,749	1,239
Fair Value	27	3
Gains/(Losses)	(10)	(3)
Assets \| Swap futures
Derivatives, Fair Value [Line Items]
Outstanding Notional	60
Fair Value	0
Gains/(Losses)	0
Assets \| Eurodollar futures
Derivatives, Fair Value [Line Items]
Outstanding Notional		6
Fair Value		0
Gains/(Losses)		0
Liabilities
Derivatives, Fair Value [Line Items]
Outstanding Notional	12,464	10,179
Derivative financial instruments	26	50
Gains/(Losses)	(131)	35
Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	9
Derivative financial instruments	0
Gains/(Losses)	0
Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional	708	55
Derivative financial instruments	1	0
Gains/(Losses)	0	(2)
Liabilities \| Forward MBS trades
Derivatives, Fair Value [Line Items]
Outstanding Notional	11,747	10,119
Derivative financial instruments	25	50
Gains/(Losses)	$ (131)	37
Liabilities \| Eurodollar futures
Derivatives, Fair Value [Line Items]
Outstanding Notional		5
Derivative financial instruments		0
Gains/(Losses)		$ 0

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

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

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

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No definition available.

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