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Commitments, Contingent Liabilities, and Guarantees - Additional Information (Details) $ in Millions		2 Months Ended	12 Months Ended
	Feb. 09, 2024 USD ($)	Dec. 31, 2023 USD ($) lawsuit	Dec. 31, 2023 USD ($)
Commitments Contingencies And Guarantees [Line Items]
Number of shareholder derivative lawsuits filed | lawsuit		2
Subsequent Event
Commitments Contingencies And Guarantees [Line Items]
Penalty charged	$ 10
Standby letters of credit
Commitments Contingencies And Guarantees [Line Items]
Remaining weighted-average life of standby letters of credit in years			1 year 7 months 6 days
Recourse agreement with FNMA
Commitments Contingencies And Guarantees [Line Items]
Weighted-average remaining term for outstanding commercial mortgage loans in years			7 years
Unpaid principal balance outstanding of loans sold		$ 24,000	$ 24,000
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding		31.00%	31.00%
Residential mortgage reserve
Commitments Contingencies And Guarantees [Line Items]
Unpaid principal balance outstanding of loans sold		$ 11,200	$ 11,200
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding		30.00%	30.00%
Liability for estimated repurchase obligations on loans sold		$ 11	$ 11
Written put options
Commitments Contingencies And Guarantees [Line Items]
Weighted average life of written put options			1 year 9 months 18 days
Minimum | Standby letters of credit
Commitments Contingencies And Guarantees [Line Items]
Remaining actual life letters of credit in years			1 year
Minimum | Low
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment			0.00%
Minimum | Moderate
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment			30.00%
Minimum | High
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment			70.00%
Maximum | Standby letters of credit
Commitments Contingencies And Guarantees [Line Items]
Remaining actual life letters of credit in years			10 years 10 months 24 days
Maximum | Low
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment			30.00%
Maximum | Moderate
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment			70.00%

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Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The total number of new claims filed pertaining to a loss contingency during the period.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
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Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
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