v3.26.1
Fair Values of Assets and Liabilities - Carrying Amounts and Fair Values of Financial Instruments (Detail) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Carrying Amount [Member]    
Fair Value Measurements Of Financial Instruments [Line Items]    
Cash and due from banks $ 118,134 $ 103,280
Interest-bearing deposits 224,806 77,082
Debt Securities, Available-for-Sale 1,042,399 1,014,194
Debt Securities, Held-to-maturity 577,286 519,422
Other investments 28,946 38,295
Loans Held for sale, Amount 31,638 271,452
Financing Receivable, before Allowance for Credit Loss 9,433,825 9,508,039
Deposits 10,409,893 10,250,969
Short-term borrowings 22,858 147,966
Subordinated debt 128,507 128,466
Long-term debt 0 129,555
Capital Lease Obligations 3,562 3,721
Estimate of Fair Value Measurement [Member]    
Fair Value Measurements Of Financial Instruments [Line Items]    
Cash and due from banks 118,134 103,280
Interest-bearing deposits 224,806 77,082
Debt Securities, Available-for-Sale 1,042,399 1,014,194
Debt Securities, Held-to-maturity 526,592 470,665
Other investments 28,946 38,295
Loans Held for sale, Amount 31,638 271,452
Financing Receivable, before Allowance for Credit Loss 9,563,777 9,657,464
Deposits 10,405,116 10,248,485
Short-term borrowings 21,220 147,926
Subordinated debt 119,873 121,747
Long-term debt 0 130,108
Capital Lease Obligations 3,562 3,721
Estimate of Fair Value Measurement [Member] | Level 1 [Member]    
Fair Value Measurements Of Financial Instruments [Line Items]    
Cash and due from banks 118,134 103,280
Interest-bearing deposits 224,806 77,082
Debt Securities, Available-for-Sale 0 0
Debt Securities, Held-to-maturity 0 0
Other investments 0 0
Loans Held for sale, Amount 0 0
Financing Receivable, before Allowance for Credit Loss 0 0
Deposits 0 0
Short-term borrowings 0 0
Subordinated debt 0 0
Long-term debt 0 0
Capital Lease Obligations 0 0
Estimate of Fair Value Measurement [Member] | Level 2 [Member]    
Fair Value Measurements Of Financial Instruments [Line Items]    
Cash and due from banks 0 0
Interest-bearing deposits 0 0
Debt Securities, Available-for-Sale 1,042,399 1,014,194
Debt Securities, Held-to-maturity 526,592 470,665
Other investments 23,214 32,563
Loans Held for sale, Amount 31,638 271,452
Financing Receivable, before Allowance for Credit Loss 47,010 40,617
Deposits 10,405,116 10,248,485
Short-term borrowings 21,220 147,926
Subordinated debt 0 0
Long-term debt 0 130,108
Capital Lease Obligations 3,562 3,721
Estimate of Fair Value Measurement [Member] | Level 3 [Member]    
Fair Value Measurements Of Financial Instruments [Line Items]    
Cash and due from banks 0 0
Interest-bearing deposits 0 0
Debt Securities, Available-for-Sale 0 0
Debt Securities, Held-to-maturity 0 0
Other investments 5,732 5,732
Loans Held for sale, Amount 0 0
Financing Receivable, before Allowance for Credit Loss 9,516,767 9,616,847
Deposits 0 0
Short-term borrowings 0 0
Subordinated debt 119,873 121,747
Long-term debt 0 0
Capital Lease Obligations 0 0
Cash and due from banks 118,134 103,280
Interest-bearing deposits 224,806 77,082
Debt Securities, Available-for-Sale 1,042,399 1,014,194
Debt Securities, Held-to-maturity 577,286 519,422
Other investments 28,946 38,295
Financing Receivable, before Allowance for Credit Loss 9,433,825 9,508,039
Deposits 10,409,893 10,250,969
Short-term borrowings 22,858 147,966
Subordinated debt 128,507 128,466
Long-term debt 0 129,555
Capital Lease Obligations $ 3,562 $ 3,721