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v3.25.1

Basis of Accounting and Consolidation - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 USD ($) Segment $ / shares shares | Sep. 30, 2024 USD ($) | Mar. 31, 2024 shares | Dec. 31, 2024 $ / shares
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Common stock, par value (in dollars per share) | $ / shares | $ 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) | 550,000 |  |  |
Employee discount for employee stock purchase plan | 15.00% |  |  |
Employee stock purchase plan, number of shares authorized | 600,000 |  |  |
Stock issued during period, shares, employee stock purchase plans | 6,891 |  | 8,612 |
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 |  |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | 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) | 46,000 |  | 39,150 |
Mid Rivers Insurance Group, Inc |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Purchase price | $ |  | $ 10,100,000 |  |

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