v3.26.1
Loans and Allowance for Credit Losses - Allowance for Credit Losses (Detail) - USD ($)
 3 Months Ended 12 Months Ended
May 01, 2025
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   $ 125,768,000 $ 118,906,000 $ 118,906,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date $ 3,560,000      
Charge-offs   (9,437,000) (8,010,000) (38,366,000)
Recoveries   1,276,000 4,912,000 8,991,000
Provision for credit losses   11,576,000 4,123,000  
Ending Balance   129,183,000 119,931,000 125,768,000
Nonaccrual Commercial Loans [Member]        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Loans Held for sale, Amount   1,100,000   0
Time and Demand Loans        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (1,917,000)   (16,182,000)
Recoveries   130,000   4,223,000
Commercial Credit Cards        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (141,000)   (302,000)
Recoveries   1,000   35,000
Senior Lien        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (106,000)   (501,000)
Recoveries   16,000   66,000
Junior Lien        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (39,000)   (244,000)
Recoveries   10,000   168,000
Multifamily        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   0   (766,000)
Recoveries   0   0
Nonowner Occupied Commercial Real Estate        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (2,016,000)   (4,770,000)
Recoveries   6,000   148,000
Owner Occupied Commercial Real Estate        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (292,000)   (1,652,000)
Recoveries   34,000   69,000
Automobiles        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (2,145,000)   (7,025,000)
Recoveries   713,000   2,992,000
Consumer Credit Cards        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (110,000)   (346,000)
Recoveries   21,000   79,000
Other Consumer Loans        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (389,000)   (1,516,000)
Recoveries   70,000   351,000
Construction Residential        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   0   (562,000)
Recoveries   0   0
Construction Other        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (326,000)   (732,000)
Recoveries   0   0
Time and Demand Loans Other        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (579,000)   (1,480,000)
Recoveries   60,000   234,000
Equipment Finance        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Charge-offs   (1,377,000)   (2,288,000)
Recoveries   215,000   626,000
Commercial, financial, agricultural and other [Member]        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   38,149,000 29,131,000 29,131,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 1,616,000      
Charge-offs   (4,014,000) (4,019,000)  
Recoveries   406,000 3,690,000  
Provision for credit losses   8,229,000 2,543,000  
Ending Balance   42,770,000 31,345,000 38,149,000
Commercial, financial, agricultural and other [Member] | Time and Demand Loans        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   22,223,000 19,433,000 19,433,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 1,616,000      
Charge-offs   (1,917,000) (2,976,000)  
Recoveries   130,000 3,484,000  
Provision for credit losses   5,431,000 459,000  
Ending Balance   25,867,000 20,400,000 22,223,000
Commercial, financial, agricultural and other [Member] | Commercial Credit Cards        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   177,000 182,000 182,000
Charge-offs   (141,000) (98,000)  
Recoveries   1,000 22,000  
Provision for credit losses   171,000 104,000  
Ending Balance   208,000 210,000 177,000
Commercial, financial, agricultural and other [Member] | Time and Demand Loans Other        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   1,611,000 1,672,000 1,672,000
Charge-offs   (579,000) (369,000)  
Recoveries   60,000 53,000  
Provision for credit losses   713,000 603,000  
Ending Balance   1,805,000 1,959,000 1,611,000
Commercial, financial, agricultural and other [Member] | Equipment Finance        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   14,138,000 7,844,000 7,844,000
Charge-offs   (1,377,000) (576,000)  
Recoveries   215,000 131,000  
Provision for credit losses   1,914,000 1,377,000  
Ending Balance   14,890,000 8,776,000 14,138,000
Residential real estate [Member]        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   21,629,000 22,396,000 22,396,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 45,000      
Charge-offs   (145,000) (108,000)  
Recoveries   26,000 137,000  
Provision for credit losses   435,000 (87,000)  
Ending Balance   21,945,000 22,338,000 21,629,000
Residential real estate [Member] | Senior Lien        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   15,056,000 15,758,000 15,758,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 38,000      
Charge-offs   (106,000) (33,000)  
Recoveries   16,000 16,000  
Provision for credit losses   401,000 (138,000)  
Ending Balance   15,367,000 15,603,000 15,056,000
Residential real estate [Member] | Junior Lien        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   6,573,000 6,638,000 6,638,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 7,000      
Charge-offs   (39,000) (75,000)  
Recoveries   10,000 121,000  
Provision for credit losses   34,000 51,000  
Ending Balance   6,578,000 6,735,000 6,573,000
Commercial Real Estate [Member]        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   40,271,000 40,232,000 40,232,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 1,087,000      
Charge-offs   (2,308,000) (1,464,000)  
Recoveries   40,000 156,000  
Provision for credit losses   1,791,000 (553,000)  
Ending Balance   39,794,000 38,371,000 40,271,000
Commercial Real Estate [Member] | Multifamily        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   5,528,000 5,431,000 5,431,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 120,000      
Charge-offs   0 0  
Recoveries   0 0  
Provision for credit losses   1,994,000 47,000  
Ending Balance   7,522,000 5,478,000 5,528,000
Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   24,865,000 23,332,000 23,332,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 943,000      
Charge-offs   (2,016,000) (874,000)  
Recoveries   6,000 110,000  
Provision for credit losses   (950,000) (754,000)  
Ending Balance   21,905,000 21,814,000 24,865,000
Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   9,878,000 11,469,000 11,469,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 24,000      
Charge-offs   (292,000) (590,000)  
Recoveries   34,000 46,000  
Provision for credit losses   747,000 154,000  
Ending Balance   10,367,000 11,079,000 9,878,000
Loans to individuals [Member]        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   17,911,000 21,117,000 21,117,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 2,000      
Charge-offs   (2,644,000) (2,419,000)  
Recoveries   804,000 929,000  
Provision for credit losses   1,502,000 1,418,000  
Ending Balance   17,573,000 21,045,000 17,911,000
Loans to individuals [Member] | Automobiles        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   14,962,000 18,693,000 18,693,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 1,000      
Charge-offs   (2,145,000) (1,805,000)  
Recoveries   713,000 846,000  
Provision for credit losses   1,225,000 1,315,000  
Ending Balance   14,755,000 19,049,000 14,962,000
Loans to individuals [Member] | Consumer Credit Cards        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   473,000 341,000 341,000
Charge-offs   (110,000) (95,000)  
Recoveries   21,000 18,000  
Provision for credit losses   51,000 59,000  
Ending Balance   435,000 323,000 473,000
Loans to individuals [Member] | Other Consumer Loans        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   2,476,000 2,083,000 2,083,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 1,000      
Charge-offs   (389,000) (519,000)  
Recoveries   70,000 65,000  
Provision for credit losses   226,000 44,000  
Ending Balance   2,383,000 1,673,000 2,476,000
Real estate construction [Member]        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   7,808,000 6,030,000 6,030,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 810,000      
Charge-offs   (326,000) 0  
Recoveries   0 0  
Provision for credit losses   (381,000) 802,000  
Ending Balance   7,101,000 6,832,000 7,808,000
Real estate construction [Member] | Construction Residential        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   690,000 114,000 114,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date 628,000      
Charge-offs   0 0  
Recoveries   0 0  
Provision for credit losses   (150,000) 43,000  
Ending Balance   540,000 157,000 690,000
Real estate construction [Member] | Construction Other        
Accounts Receivable, Allowance for Credit Loss [Roll Forward]        
Beginning Balance   7,118,000 5,916,000 5,916,000
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date $ 182,000      
Charge-offs   (326,000) 0  
Recoveries   0 0  
Provision for credit losses   (231,000) 759,000  
Ending Balance   $ 6,561,000 $ 6,675,000 $ 7,118,000