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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 | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fixed income securities, held-to-maturity - fair value | $ 24,800 | $ 24,735
Commercial mortgage loans, fair value | 251,498 | 224,842
Long-term debt, fair value | 895,247 | 489,694
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
Significant Other Observable Inputs (Level 2) |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fixed income securities, held-to-maturity - fair value | 24,800 | 24,735
Commercial mortgage loans, fair value | 0 | 0
Long-term debt, fair value | 895,247 | 489,694
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 | 251,498 | 224,842
Long-term debt, fair value | $ 0 | $ 0
7.25% Senior Notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest Rate | 7.25% | 7.25%
Long-term debt, fair value | $ 55,396 | $ 54,657
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 | 55,396 | 54,657
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
5.90% Senior Notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest Rate | 5.90% |
Long-term debt, fair value | $ 402,291 | $ 0
5.90% 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 |
5.90% Senior Notes | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt, fair value | 402,291 |
5.90% Senior Notes | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt, fair value | $ 0 |
6.70% Senior Notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest Rate | 6.70% | 6.70%
Long-term debt, fair value | $ 104,846 | $ 103,057
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 | 104,846 | 103,057
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%
Long-term debt, fair value | $ 273,711 | $ 273,464
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 | 273,711 | 273,464
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%
Long-term debt, fair value | $ 59,003 | $ 58,516
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 | 59,003 | 58,516
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
Corporate securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fixed income securities, held-to-maturity - fair value | 24,800 | 24,735
Corporate securities | 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
Corporate securities | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fixed income securities, held-to-maturity - fair value | 24,800 | 24,735
Corporate securities | 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

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