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Commitments and Contingencies - Schedule of Loan Commitments and Letters of Credit (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Loss Contingencies [Line Items] |  |
Carry amount included in other assets | $ 806,987 | $ 672,803
Permanent and short-term construction loans and letter of credit unfunded commitments | 333,625 | 205,855
Funded portion of permanent and short-term loans and letters of credit | 187,048 | 229,668
Future funding commitment amount | 426,700 | 358,500
Letters of credit |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 417,621 | 340,385
Contractual amount net of risk participations | 15,700 | 16,800
Commitments to fund commercial and industrial loans |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 10,000,222 | 9,956,797
Commitments to fund commercial real estate, construction, and land development loans |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 2,193,892 | 2,135,638
Commitments under home equity lines of credit |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 2,107,011 | 2,119,616
Unused credit card lines |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 448,642 | 446,800
Other loan commitments |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 554,841 | 621,659
Total letters of credit and unfunded lending commitments |  |
Loss Contingencies [Line Items] |  |
Total letters of credit and unfunded lending commitments | 15,722,229 | 15,620,895
Permanent and Short-Term Construction Loans and Letter of Credit Commitments |  |
Loss Contingencies [Line Items] |  |
Contractual amount net of risk participations | 14,800 | 16,000
Funded Portion of Permanent and Short-Term Loans and Letters of Credit |  |
Loss Contingencies [Line Items] |  |
Contractual amount net of risk participations | $ 18,000 | $ 16,200

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