v3.26.1
Loans and Allowance for Credit Losses (Allowance for Credit Losses by Portfolio Class) (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     $ 307,731 $ 318,882
Allowance for loan losses: Net provision for loan losses $ 13,775 $ 14,925 26,947 25,387
Allowance for loan losses: Ending balance 312,608 313,189 312,608 313,189
Reserve for unfunded lending commitments: Beginning balance     33,928 24,053
Reserve for unfunded lending commitments: Provision for losses     1,491 (3,047)
Reserve for unfunded lending commitments: Ending balance 35,419 27,100 35,419 27,100
Total allowance for credit losses 348,027 340,289 348,027 340,289
Allowance for credit losses: Individually evaluated 6,554 10,618 6,554 10,618
Allowance for credit losses: Collectively evaluated 341,473 329,671 341,473 329,671
Non-Purchased Credit Impaired Loans [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (25,574) (35,621)
Allowance for loan losses: Recoveries     4,995 7,588
Allowance for loan losses: Net provision for loan losses     25,456 22,340
Total Commercial [Member] | Commercial Real Estate - Income Producing [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     60,475 71,975
Allowance for loan losses: Ending balance 58,709 65,335 58,709 65,335
Reserve for unfunded lending commitments: Beginning balance     1,005 642
Reserve for unfunded lending commitments: Provision for losses     (357) (152)
Reserve for unfunded lending commitments: Ending balance 648 490 648 490
Total allowance for credit losses 59,357 65,825 59,357 65,825
Allowance for credit losses: Collectively evaluated 59,357 65,825 59,357 65,825
Total Commercial [Member] | Construction and Land Development [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     17,450 21,158
Allowance for loan losses: Ending balance 19,422 17,685 19,422 17,685
Reserve for unfunded lending commitments: Beginning balance     17,949 14,639
Reserve for unfunded lending commitments: Provision for losses     848 (1,483)
Reserve for unfunded lending commitments: Ending balance 18,797 16,122 18,797 16,122
Total allowance for credit losses 38,219 33,807 38,219 33,807
Allowance for credit losses: Collectively evaluated 38,219 33,807 38,219 33,807
Total Commercial [Member] | Non-Purchased Credit Impaired Loans [Member] | Commercial Real Estate - Income Producing [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs       (34)
Allowance for loan losses: Recoveries     6 0
Allowance for loan losses: Net provision for loan losses     (1,772) 6,606
Total Commercial [Member] | Non-Purchased Credit Impaired Loans [Member] | Construction and Land Development [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (248) (33)
Allowance for loan losses: Recoveries     2 123
Allowance for loan losses: Net provision for loan losses     2,218 (3,563)
Total Commercial [Member] | Total Commercial And Industrial [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     162,134 157,354
Allowance for loan losses: Ending balance 168,873 160,314 168,873 160,314
Reserve for unfunded lending commitments: Beginning balance     13,010 6,750
Reserve for unfunded lending commitments: Provision for losses     1,122 1,996
Reserve for unfunded lending commitments: Ending balance 14,132 8,746 14,132 8,746
Total allowance for credit losses 183,005 169,060 183,005 169,060
Allowance for credit losses: Individually evaluated 6,554 9,667 6,554 9,667
Allowance for credit losses: Collectively evaluated 176,451 159,393 176,451 159,393
Total Commercial [Member] | Total Commercial And Industrial [Member] | Commercial Non-Real Estate [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     121,439 121,090
Allowance for loan losses: Ending balance 125,346 122,601 125,346 122,601
Reserve for unfunded lending commitments: Beginning balance     12,639 6,441
Reserve for unfunded lending commitments: Provision for losses     1,176 1,963
Reserve for unfunded lending commitments: Ending balance 13,815 8,404 13,815 8,404
Total allowance for credit losses 139,161 131,005 139,161 131,005
Allowance for credit losses: Individually evaluated 6,380 9,626 6,380 9,626
Allowance for credit losses: Collectively evaluated 132,781 121,379 132,781 121,379
Total Commercial [Member] | Total Commercial And Industrial [Member] | Commercial Real Estate - Owner Occupied        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     40,695 36,264
Allowance for loan losses: Ending balance 43,527 37,713 43,527 37,713
Reserve for unfunded lending commitments: Beginning balance     371 309
Reserve for unfunded lending commitments: Provision for losses     (54) (33)
Reserve for unfunded lending commitments: Ending balance 317 342 317 342
Total allowance for credit losses 43,844 38,055 43,844 38,055
Allowance for credit losses: Individually evaluated 174 41 174 41
Allowance for credit losses: Collectively evaluated 43,670 38,014 43,670 38,014
Total Commercial [Member] | Total Commercial And Industrial [Member] | Non-Purchased Credit Impaired Loans [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (16,868) (27,225)
Allowance for loan losses: Recoveries     3,016 5,405
Allowance for loan losses: Net provision for loan losses     20,591 24,780
Total Commercial [Member] | Total Commercial And Industrial [Member] | Non-Purchased Credit Impaired Loans [Member] | Commercial Non-Real Estate [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (16,860) (24,484)
Allowance for loan losses: Recoveries     2,684 5,042
Allowance for loan losses: Net provision for loan losses     18,083 20,953
Total Commercial [Member] | Total Commercial And Industrial [Member] | Non-Purchased Credit Impaired Loans [Member] | Commercial Real Estate - Owner Occupied        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (8)  
Allowance for loan losses: Recoveries     332 363
Allowance for loan losses: Net provision for loan losses     2,508 (3,827)
Residential Mortgages [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     42,834 42,445
Allowance for loan losses: Ending balance 42,259 43,617 42,259 43,617
Reserve for unfunded lending commitments: Beginning balance     3 4
Reserve for unfunded lending commitments: Provision for losses     (3) 3
Reserve for unfunded lending commitments: Ending balance   1   1
Total allowance for credit losses 42,259 43,618 42,259 43,618
Allowance for credit losses: Individually evaluated   753   753
Allowance for credit losses: Collectively evaluated 42,259 42,865 42,259 42,865
Residential Mortgages [Member] | Non-Purchased Credit Impaired Loans [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (531) (429)
Allowance for loan losses: Recoveries     203 453
Allowance for loan losses: Net provision for loan losses     (247) 1,148
Consumer [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Beginning balance     24,838 25,950
Allowance for loan losses: Ending balance 23,345 26,238 23,345 26,238
Reserve for unfunded lending commitments: Beginning balance     1,961 2,018
Reserve for unfunded lending commitments: Provision for losses     (119) (277)
Reserve for unfunded lending commitments: Ending balance 1,842 1,741 1,842 1,741
Total allowance for credit losses 25,187 27,979 25,187 27,979
Allowance for credit losses: Individually evaluated   198   198
Allowance for credit losses: Collectively evaluated $ 25,187 $ 27,781 25,187 27,781
Consumer [Member] | Non-Purchased Credit Impaired Loans [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Allowance for loan losses: Charge-offs     (7,927) (7,900)
Allowance for loan losses: Recoveries     1,768 1,607
Allowance for loan losses: Net provision for loan losses     $ 4,666 $ 6,581