Fair Value Measurements - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Net fair value of the interest rate lock commitments	$ 1,000,000
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bps	2,000,000
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bps	3,000,000
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bps	2,000,000
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bps	4,000,000
Change in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	0
Change in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	0
Private equity, observable price change adjustment	4,000,000	$ 41,000,000
Private equity, cumulative observable price change	40,000,000
Private equity, impairment	12,000,000	3,000,000
Private equity, cumulative impairment	34,000,000
Fair value of embedded derivatives	0	89,000,000
Gain on embedded derivatives	11,000,000
Loss on embedded derivatives		3,000,000
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	0	(1,000,000)
Other Real Estate Owned \| Transfer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value gains (losses)	0	(5,000,000)
Commercial \| Commercial loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	(1,000,000)	1,000,000
Fair value gains (losses)	0	1,000,000
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	(10,000,000)	28,000,000
FVO valuation adjustments related to instrument-specific credit risk	$ 1,000,000	$ 0

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.

+ References

No definition available.

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

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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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This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

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

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