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Loans and allowance for loan losses - Additional Information (Detail) - USD ($) $ in Millions | Jun. 30, 2026 | Dec. 31, 2025
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Loans And Leases Receivable [Line Items] |  |
Loans secured by residential real estate that were in the process of foreclosure | $ 186 | $ 182
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed | 59.00% |
Financing receivable, accrued interest, before allowance for credit loss | $ 625 | $ 627

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- Definition Loans and leases receivable. + References No definition available. + Details
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- Definition Percentage of loans in the process of foreclosure, serviced by other entities, classified as government guaranteed. + References No definition available. + Details
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- Definition Residential mortgage loans secured by residential real estate in process of foreclosure. + References No definition available. + Details
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- Definition Amount, before allowance for credit loss, of accrued interest on financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
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