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Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Jun. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | $ 92,426 | $ 100,865 | $ 91,060 | $ 91,060 | $ 96,868 | $ 96,868
Charge-offs | 32,206 | 11,226 |  | 40,754 | 21,615 |
Recoveries | 823 | 1,706 |  | 4,343 | 6,567 |
Provision | 35,216 | 4,644 |  | 41,610 | 14,169 |
Ending balance | 96,259 | 95,989 | 92,426 | 96,259 | 95,989 | 91,060
Average balance | $ 7,523,624 | $ 7,930,996 |  | $ 7,564,411 | $ 7,872,235 |
Net charge-offs to loan average balance (annualized) | 1.65% | 0.48% |  | 0.64% | 0.26% |
Provision for credit losses | $ 36,800 | $ 4,600 |  | $ 43,100 | $ 12,800 |
Provision (release) for loan credit losses | 35,216 | 4,644 |  | 41,610 | 14,169 |
Provision (benefit) for off-balance sheet commitments | 1,600 | (36) |  | 1,500 | (1,300) |
Provision (benefit) for held to maturity securities | (4) | (5) |  | (7) | (11) |
Real estate | Commercial Real Estate |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 16,785 | 17,244 | 16,546 | 16,546 | 19,625 | 19,625
Charge-offs | 0 | 0 |  | 728 | 480 | 480
Recoveries | 5 | 21 |  | 18 | 318 |
Provision | 1,386 | (435) |  | 2,340 | (2,633) |
Ending balance | 18,176 | 16,830 | 16,785 | 18,176 | 16,830 | 16,546
Average balance | $ 2,450,148 | $ 2,507,566 |  | $ 2,435,301 | $ 2,481,274 |
Net charge-offs to loan average balance (annualized) | 0.00% | 0.00% |  | 0.04% | 0.01% |
Provision (release) for loan credit losses | $ 1,386 | $ (435) |  | $ 2,340 | $ (2,633) |
Real estate | Construction/ Land/ Land Development |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 6,324 | 9,274 | 7,398 | 7,398 | 9,990 | 9,990
Charge-offs | 0 | 0 |  | 0 | 0 | 0
Recoveries | 0 | 0 |  | 0 | 0 |
Provision | 1,417 | (546) |  | 343 | (1,262) |
Ending balance | 7,741 | 8,728 | 6,324 | 7,741 | 8,728 | 7,398
Average balance | $ 644,455 | $ 1,019,302 |  | $ 734,621 | $ 1,069,360 |
Net charge-offs to loan average balance (annualized) | 0.00% | 0.00% |  | 0.00% | 0.00% |
Provision (release) for loan credit losses | $ 1,417 | $ (546) |  | $ 343 | $ (1,262) |
Real estate | Residential Real Estate |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 13,639 | 11,780 | 12,454 | 12,454 | 10,619 | 10,619
Charge-offs | 0 | 11 |  | 119 | 11 | 11
Recoveries | 3 | 4 |  | 56 | 12 |
Provision | 722 | 302 |  | 1,973 | 1,455 |
Ending balance | 14,364 | 12,075 | 13,639 | 14,364 | 12,075 | 12,454
Average balance | $ 1,992,766 | $ 1,824,725 |  | $ 1,953,007 | $ 1,784,035 |
Net charge-offs to loan average balance (annualized) | 0.00% | 0.00% |  | 0.00% | 0.00% |
Provision (release) for loan credit losses | $ 722 | $ 302 |  | $ 1,973 | $ 1,455 |
Commercial and industrial |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 54,175 | 61,184 | 53,449 | 53,449 | 55,330 | 55,330
Charge-offs | 32,184 | 11,195 |  | 39,740 | 21,044 | 22,787
Recoveries | 812 | 1,680 |  | 4,244 | 6,228 |
Provision | 31,679 | 5,070 |  | 36,529 | 16,225 |
Ending balance | 54,482 | 56,739 | 54,175 | 54,482 | 56,739 | 53,449
Average balance | $ 1,994,755 | $ 2,071,984 |  | $ 2,022,286 | $ 2,107,195 |
Net charge-offs to loan average balance (annualized) | 6.24% | 1.83% |  | 2.35% | 0.94% |
Provision (release) for loan credit losses | $ 31,679 | $ 5,070 |  | $ 36,529 | $ 16,225 |
Mortgage Warehouse Lines of Credit |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 780 | 676 | 501 | 501 | 529 | 529
Charge-offs | 0 | 0 |  | 0 | 0 | 0
Recoveries | 0 | 0 |  | 0 | 0 |
Provision | 47 | (13) |  | 326 | 134 |
Ending balance | 827 | 663 | 780 | 827 | 663 | 501
Average balance | $ 420,848 | $ 484,680 |  | $ 397,466 | $ 407,553 |
Net charge-offs to loan average balance (annualized) | 0.00% | 0.00% |  | 0.00% | 0.00% |
Provision (release) for loan credit losses | $ 47 | $ (13) |  | $ 326 | $ 134 |
Consumer |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 723 | 707 | 712 | 712 | 775 | 775
Charge-offs | 22 | 20 |  | 167 | 80 | 362
Recoveries | 3 | 1 |  | 25 | 9 |
Provision | (35) | 266 |  | 99 | 250 |
Ending balance | 669 | 954 | $ 723 | 669 | 954 | $ 712
Average balance | $ 20,652 | $ 22,739 |  | $ 21,730 | $ 22,818 |
Net charge-offs to loan average balance (annualized) | 0.37% | 0.33% |  | 0.87% | 0.42% |
Provision (release) for loan credit losses | $ (35) | $ 266 |  | $ 99 | $ 250 |

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