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Loans and allowance for loan losses - Summary of Payment Status of Loans Modified (Detail) - USD ($) $ in Thousands | Jun. 30, 2026 | Jun. 30, 2025
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | $ 1,336,000 | $ 1,466,000
Guaranteed by Government-Related Entities |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Modified past due 30-89 days | 30,000 | 40,000
Modified past due 90 days or more | 43,000 | 35,000
Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,106,000 | 1,247,000
30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 172,000 | 109,000
Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 58,000 | 110,000
Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 263,000 | 351,000
Commercial and industrial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 247,000 | 281,000
Commercial and industrial | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 8,000 | 7,000
Commercial and industrial | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 8,000 | 63,000
Commercial real estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 578,000 | 653,000
Commercial real estate | Commercial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 458,000 | 598,000
Commercial real estate | Commercial | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 117,000 | 54,000
Commercial real estate | Commercial | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 3,000 | 1,000
Commercial real estate | Residential builder and developer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 12,000 | 0
Commercial real estate | Residential builder and developer | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 3,000 | 0
Commercial real estate | Residential builder and developer | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 9,000 | 0
Commercial real estate | Residential builder and developer | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Commercial real estate | Other commercial construction |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 274,000 | 284,000
Commercial real estate | Other commercial construction | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 272,000 | 279,000
Commercial real estate | Other commercial construction | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 2,000 | 0
Commercial real estate | Other commercial construction | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 5,000
Residential real estate | Residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 196,000 | 166,000
Residential real estate | Residential | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 113,000 | 77,000
Residential real estate | Residential | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 36,000 | 48,000
Residential real estate | Residential | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 47,000 | 41,000
Consumer | Home equity lines and loans (e) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 2,000 | 1,000
Consumer | Home equity lines and loans (e) | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 2,000 | 1,000
Consumer | Home equity lines and loans (e) | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Home equity lines and loans (e) | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Recreational finance |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 1,000
Consumer | Recreational finance | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 1,000
Consumer | Recreational finance | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Recreational finance | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 11,000 | 10,000
Consumer | Other | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 11,000 | 10,000
Consumer | Other | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Other | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | $ 0 | $ 0

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