Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Net fair value of the interest rate lock commitments	$ 5
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bps	1
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bps	3
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bps	2
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bps	3
Change in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	0
Change in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	0
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	0	$ 4
Private equity, cumulative observable price change	40
Private equity, impairment	2	12
Private equity, cumulative impairment	15
Fair value of embedded derivatives	0	0
Gain on embedded derivatives	0	11
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	(8)	0
Other Real Estate Owned \| Transferred at Point in Time [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value gains (losses)	0	0
Commercial \| Commercial loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	0	1
Fair value gains (losses)	0	0
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	6	10
FVO valuation adjustments related to instrument-specific credit risk	$ 0	$ 1

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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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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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Amount of impairment loss on investment in equity security without readily determinable fair value.

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Amount of cumulative impairment loss 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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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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