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Fair Value Measurements - Schedule of Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2019 | Dec. 31, 2016 | Nov. 30, 2005 | Nov. 30, 2004
--- | --- | --- | --- | --- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | $ 24,735 | $ 21,923 |  |  |  |
Commercial mortgage loans, fair value | 224,842 | 178,913 |  |  |  |
Long-term debt, fair value | 489,694 | 503,805 |  |  |  |
Obligations of states and political subdivisions |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value |  | 0 |  |  |  |
Corporate securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | 24,735 | 21,923 |  |  |  |
Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | 0 | 0 |  |  |  |
Commercial mortgage loans, fair value | 0 | 0 |  |  |  |
Long-term debt, fair value | 0 | 0 |  |  |  |
Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) | Obligations of states and political subdivisions |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value |  | 0 |  |  |  |
Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) | Corporate securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | 0 | 0 |  |  |  |
Significant Other Observable Inputs (Level 2) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | 24,735 | 21,923 |  |  |  |
Commercial mortgage loans, fair value | 0 | 0 |  |  |  |
Long-term debt, fair value | 489,694 | 503,805 |  |  |  |
Significant Other Observable Inputs (Level 2) | Obligations of states and political subdivisions |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value |  | 0 |  |  |  |
Significant Other Observable Inputs (Level 2) | Corporate securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | 24,735 | 21,923 |  |  |  |
Significant Unobservable Inputs (Level 3) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | 0 | 0 |  |  |  |
Commercial mortgage loans, fair value | 224,842 | 178,913 |  |  |  |
Long-term debt, fair value | 0 | 0 |  |  |  |
Significant Unobservable Inputs (Level 3) | Obligations of states and political subdivisions |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value |  | 0 |  |  |  |
Significant Unobservable Inputs (Level 3) | Corporate securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Fixed income securities, held-to-maturity - fair value | $ 0 | $ 0 |  |  |  |
7.25% Senior Notes |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Interest Rate | 7.25% | 7.25% |  |  |  | 7.25%
Long-term debt, fair value | $ 54,657 | $ 53,047 |  |  |  |
7.25% Senior Notes | Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 0 | 0 |  |  |  |
7.25% Senior Notes | Significant Other Observable Inputs (Level 2) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 54,657 | 53,047 |  |  |  |
7.25% Senior Notes | Significant Unobservable Inputs (Level 3) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | $ 0 | $ 0 |  |  |  |
6.70% Senior Notes |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Interest Rate | 6.70% | 6.70% |  |  | 6.70% |
Long-term debt, fair value | $ 103,057 | $ 104,039 |  |  |  |
6.70% Senior Notes | Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 0 | 0 |  |  |  |
6.70% Senior Notes | Significant Other Observable Inputs (Level 2) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 103,057 | 104,039 |  |  |  |
6.70% Senior Notes | Significant Unobservable Inputs (Level 3) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | $ 0 | $ 0 |  |  |  |
5.375% Senior Notes |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Interest Rate | 5.375% | 5.375% | 5.375% |  |  |
Long-term debt, fair value | $ 273,464 | $ 288,787 |  |  |  |
5.375% Senior Notes | Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 0 | 0 |  |  |  |
5.375% Senior Notes | Significant Other Observable Inputs (Level 2) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 273,464 | 288,787 |  |  |  |
5.375% Senior Notes | Significant Unobservable Inputs (Level 3) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | $ 0 | $ 0 |  |  |  |
3.03% Borrowings from FHLBI |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Interest Rate | 3.03% | 3.03% |  | 3.03% |  |
Long-term debt, fair value | $ 58,516 | $ 57,932 |  |  |  |
3.03% Borrowings from FHLBI | Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 0 | 0 |  |  |  |
3.03% Borrowings from FHLBI | Significant Other Observable Inputs (Level 2) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | 58,516 | 57,932 |  |  |  |
3.03% Borrowings from FHLBI | Significant Unobservable Inputs (Level 3) |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Long-term debt, fair value | $ 0 | $ 0 |  |  |  |

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