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v3.25.2

Basis of Accounting and Consolidation - Additional Information (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 $ / shares shares | Sep. 30, 2024 USD ($) | Jun. 30, 2024 shares | Jun. 30, 2025 USD ($) Segment $ / shares shares | Jun. 30, 2024 shares | Dec. 31, 2024 $ / shares
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Common stock, par value (in dollars per share) | $ / shares | $ 4 |  |  | $ 4 |  | $ 4
Number of operating segment | Segment |  |  |  | 1 |  |
Stock plans, term |  |  |  | 10 years |  |
Maximum number of shares to be issued in stock incentive plan (in shares) | 1,000,000 |  |  | 1,000,000 |  |
Employee discount for employee stock purchase plan |  |  |  | 15.00% |  |
Employee stock purchase plan, number of shares authorized | 600,000 |  |  | 600,000 |  |
Stock issued during period, shares, employee stock purchase plans | 7,079 |  | 7,323 | 13,970 | 15,935 |
Captive maximum gross premiums | $ |  |  |  | $ 2,850,000 |  |
ASU 2023-07 |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] | true |  |  | true |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | Dec. 31, 2024 |  |  | Dec. 31, 2024 |  |
Employee Stock Option |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Common stock awarded in SI plan (in shares) |  |  |  | 0 |  |
Restricted Stock |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Common stock awarded in SI plan (in shares) |  |  |  | 79,635 | 53,766 |
Restricted Stock Units (RSUs) |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Common stock awarded in SI plan (in shares) |  |  |  | 53,130 | 39,150 |
Mid Rivers Insurance Group, Inc |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Purchase price | $ |  | $ 10,100,000 |  |  |  |

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