Fair Value Measurements - Schedule of Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity, fair value	$ 19,540	$ 23,939
Commercial mortgage loans, fair value	267,408	274,895
Long-term debt, fair value	914,679	924,252
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	19,540	23,939
Commercial mortgage loans, fair value	0	0
Long-term debt, fair value	914,679	924,252
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	267,408	274,895
Long-term debt, fair value	0	0
3.03% borrowings from FHLBI
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 59,685	$ 59,625
Interest rate (as a percent)	3.03%	3.03%
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	59,685	59,625
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
Senior Notes \| 7.25% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 56,471	$ 56,973
Interest rate (as a percent)	7.25%	7.25%
Senior Notes \| 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
Senior Notes \| 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	56,471	56,973
Senior Notes \| 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
Senior Notes \| 6.70% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 107,389	$ 110,244
Interest rate (as a percent)	6.70%	6.70%
Senior Notes \| 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
Senior Notes \| 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	107,389	110,244
Senior Notes \| 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
Senior Notes \| 5.90% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 414,623	419,869
Interest rate (as a percent)	5.90%
Senior Notes \| 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	0
Senior Notes \| 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	414,623	419,869
Senior Notes \| 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	0
Senior Notes \| 5.375% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 276,511	$ 277,541
Interest rate (as a percent)	5.375%	5.375%
Senior Notes \| 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
Senior Notes \| 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	276,511	277,541
Senior Notes \| 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
Corporate securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity, fair value	19,540	23,939
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	19,540	23,939
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

Fair value of investment in commercial loan measured at original cost.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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