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Loans and Allowance for Credit Losses - Summary of Collateral Dependent Loans (Details) - USD ($) $ in Thousands | Jun. 30, 2026 | Mar. 31, 2026 | Dec. 31, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024
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Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ (213,724) | $ (172,427) | $ (169,530) | $ (164,794) | $ (183,178) | $ (176,994)
Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 5,881 |  | 4,573 |  |  |
Allowance for credit losses | (84) |  | (93) |  |  |
Real Estate | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 5,778 |  | 4,383 |  |  |
Business Assets | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 103 |  | 190 |  |  |
Commercial and industrial loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Allowance for credit losses | (6,882) | (7,728) | (8,757) | (8,754) | (10,066) | (11,051)
Commercial and industrial loans | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 103 |  | 190 |  |  |
Allowance for credit losses | (84) |  | (93) |  |  |
Commercial and industrial loans | Real Estate | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 0 |  | 0 |  |  |
Commercial and industrial loans | Business Assets | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 103 |  | 190 |  |  |
Real Estate Portfolio Segment | Residential real estate loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Allowance for credit losses | (10,659) | (8,498) | (11,100) | (12,224) | (13,443) | (12,250)
Real Estate Portfolio Segment | Residential real estate loans | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 1,434 |  | 39 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Real Estate Portfolio Segment | Residential real estate loans | Real Estate | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 1,434 |  | 39 |  |  |
Real Estate Portfolio Segment | Residential real estate loans | Business Assets | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 0 |  | 0 |  |  |
Real Estate Portfolio Segment | Commercial real estate loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Allowance for credit losses | (5,712) | (6,010) | (5,496) | (7,300) | (8,110) | (8,456)
Real Estate Portfolio Segment | Commercial real estate loans | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 4,344 |  | 4,344 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Real Estate Portfolio Segment | Commercial real estate loans | Real Estate | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 4,344 |  | 4,344 |  |  |
Real Estate Portfolio Segment | Commercial real estate loans | Business Assets | Collateral Dependent Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually evaluted for credit losses | 0 |  | 0 |  |  |
Construction, land and land development loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ (3,990) | $ (6,101) | $ (6,580) | $ (5,265) | $ (4,531) | $ (3,439)

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