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Loans and allowance for loan losses - Summary of Pledged Loans (Detail) - Asset Pledged as Collateral without Right - USD ($) $ in Thousands | Jun. 30, 2026 | Dec. 31, 2025
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Commercial and industrial |  |
Loans And Leases Receivable [Line Items] |  |
Pledged financial instruments | $ 23,600,000 | $ 20,700,000
Commercial real estate |  |
Loans And Leases Receivable [Line Items] |  |
Pledged financial instruments | 13,300,000 | 13,400,000
Residential real estate |  |
Loans And Leases Receivable [Line Items] |  |
Pledged financial instruments | 19,600,000 | 19,500,000
Consumer |  |
Loans And Leases Receivable [Line Items] |  |
Pledged financial instruments | $ 17,400,000 | $ 18,200,000

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- Definition Loans and leases receivable. + References No definition available. + Details
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- Definition The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 940 -SubTopic 320 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479035/940-320-45-2 + Details
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