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Commitments, Contingent Liabilities, and Guarantees - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Commitments Contingencies And Guarantees [Line Items] |  |  |
Reserve for potential losses | $ 313 | $ 290 | $ 296
Standby letters of credit |  |  |
Commitments Contingencies And Guarantees [Line Items] |  |  |
Remaining weighted-average life of standby letters of credit in years | 2 years |  |
Recourse agreement with FNMA |  |  |
Commitments Contingencies And Guarantees [Line Items] |  |  |
Weighted-average remaining term for outstanding commercial mortgage loans in years | 5 years 10 months 24 days |  |
Unpaid principal balance outstanding of loans sold | $ 25,100 |  |
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding | 33.00% |  |
Reserve for potential losses | $ 57 |  |
Residential mortgage reserve |  |  |
Commitments Contingencies And Guarantees [Line Items] |  |  |
Unpaid principal balance outstanding of loans sold | $ 11,400 |  |
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding | 30.00% |  |
Liability for estimated repurchase obligations on loans sold | $ 8 |  |
Written options |  |  |
Commitments Contingencies And Guarantees [Line Items] |  |  |
Weighted average life of written put options | 1 year 8 months 12 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 | 8 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 Weighted average life of written put options. + References No definition available. + Details
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- Definition Weighted-average remaining term for outstanding commercial mortgage loans. + References No definition available. + Details
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- Definition Amount, including accrued interest, to be repaid to counterparty to repurchase agreement when carrying amount or market value if higher, of security or other asset sold under 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 S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-7 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481444/860-30-45-2 Reference 4: 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 5: 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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- Definition Indicates, if estimable, (as a percentage) the approximate extent to which the proceeds from liquidation of any assets held either as collateral or by third parties would be expected to cover the maximum potential amount of future payments under the guarantee or each group of similar guarantees. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482425/460-10-50-4 + Details
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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482454/460-10-45-1 + Details
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