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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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- Definition Guarantor Obligations, Maximum Exposure, Undiscounted as Percentage of Total Loans Outstanding + References No definition available. + Details
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- Definition Remaining actual life letters of credit. + References No definition available. + Details
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- Definition 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 -Paragraph 1 -Subparagraph (SX 210.4-08(m)(1)(i)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(m)(1)(ii)(A)(ii)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 + Details
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