Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Net fair value of the interest rate lock commitments	$ 12
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bps	5
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bps	9
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bps	5
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bps	11
Change in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	1
Change in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	2
Change in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	1
Change in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	2
Private equity, observable price change adjustment	41	$ 23
Private equity, cumulative observable price change	68
Private equity, impairment	3	9
Private equity, cumulative impairment	24
Fair value of embedded derivatives	89
Loss on embedded derivatives	3
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	(1)	(4)
Other Real Estate Owned \| Transfer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value gains (losses)	(5)	(3)
Commercial \| Commercial loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	1	(5)
Fair value gains (losses)	1
Residential Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value changes included in earnings for instruments for which the fair value option was elected	$ 28	75
FVO valuation adjustments related to instrument-specific credit risk		$ 1

Sensitivity analysis of decrease in fair value of derivatives impact of fifty basis point increase in interest rate.

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Sensitivity analysis of decrease in fair value of derivatives impact of twenty five basis point increase in interest rate.

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Sensitivity analysis of increase in fair value of derivatives impact of fifty basis point decrease in interest rate.

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Sensitivity analysis of increase in fair value of derivatives impact of ten percent changes in assumed loan closing rates.

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Sensitivity analysis of increase in fair value of derivatives impact of twenty five basis point decrease in interest rate.

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Sensitivity analysis of increase in fair value of derivatives impact of twenty percent changes in assumed loan closing rates.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

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Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value.

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Amount of cumulative loss from downward price adjustment on investment in equity security without readily determinable fair value.

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value.

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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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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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Amount of gain (loss) related to nonoperating activities, classified as other.

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The hypothetical financial impact of a 10 percent adverse change of the specified assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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The hypothetical financial impact of a 20 percent adverse change of the specified assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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