Commitments and contingencies - Additional Information (Detail) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
Dec. 17, 2025 |
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| Loss Contingencies [Line Items] | |||
| Commitments to extend credit to commercial customers | $ 12,900 | $ 12,900 | |
| Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program | 4,700 | 4,600 | |
| Loss contingency accrual | 0 | $ 22 | |
| Tricolor Holdings, LLC | |||
| Loss Contingencies [Line Items] | |||
| Fictitious loans | $ 683 | ||
| Maximum | |||
| Loss Contingencies [Line Items] | |||
| Range of reasonably possible losses | $ 25 |
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- Definition Commitments And Contingencies, Fictitious Loans No definition available.
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- Definition Commitments to extend credit to commercial customers. No definition available.
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- Definition Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program. No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of loss contingency liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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