v3.25.2
Loans and allowance for loan losses - Summary of Payment Status of Loans Modified (Detail) - USD ($)
$ in Thousands
Jun. 30, 2025
Jun. 30, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost $ 1,466,000 $ 1,482,000
Guaranteed by Government-Related Entities    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Modified past due 30-89 days 40,000 45,000
Modified past due 90 days or more 35,000 27,000
Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 1,247,000 1,323,000
30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 109,000 113,000
Accruing Loans Past Due 90 Days or More    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 110,000 46,000
Commercial and industrial    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 351,000 312,000
Commercial and industrial | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 281,000 294,000
Commercial and industrial | 30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 7,000 15,000
Commercial and industrial | Accruing Loans Past Due 90 Days or More    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 63,000 3,000
Commercial Real Estate | Commercial    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 653,000 601,000
Commercial Real Estate | Commercial | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 598,000 545,000
Commercial Real Estate | Commercial | 30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 54,000 42,000
Commercial Real Estate | Commercial | Accruing Loans Past Due 90 Days or More    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 1,000 14,000
Commercial Real Estate | Residential builder and developer    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 0 28,000
Commercial Real Estate | Residential builder and developer | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 0 28,000
Commercial Real Estate | Residential builder and developer | 30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 0 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 284,000 346,000
Commercial Real Estate | Other commercial construction | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 279,000 344,000
Commercial Real Estate | Other commercial construction | 30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 0 2,000
Commercial Real Estate | Other commercial construction | Accruing Loans Past Due 90 Days or More    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 5,000 0
Residential Real Estate | Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 166,000 193,000
Residential Real Estate | Residential | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 77,000 110,000
Residential Real Estate | Residential | 30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 48,000 54,000
Residential Real Estate | Residential | Accruing Loans Past Due 90 Days or More    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 41,000 29,000
Consumer | Home equity lines and loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 1,000 2,000
Consumer | Home equity lines and loans | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 1,000 2,000
Consumer | Home equity lines and loans | 30-89 Days Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 0 0
Consumer | Home equity lines and loans | 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 1,000 0
Consumer | Recreational finance | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 1,000 0
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 10,000 0
Consumer | Other | Current    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Amortized cost 10,000 0
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