Fair Value Measurements - Schedule of Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	$ 21,440	$ 21,923
Commercial mortgage loans, fair value	218,599	178,913
Long-term debt, fair value	517,310	503,805
Corporate securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	21,440	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) \| 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	21,440	21,923
Commercial mortgage loans, fair value	0	0
Long-term debt, fair value	517,310	503,805
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	21,440	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	218,599	178,913
Long-term debt, fair value	0	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%
Long-term debt, fair value	$ 54,828	$ 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	54,828	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%
Long-term debt, fair value	$ 106,814	$ 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	106,814	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%
Long-term debt, fair value	$ 296,608	$ 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	296,608	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%
Long-term debt, fair value	$ 59,060	$ 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	59,060	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

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.

+ References

No definition available.

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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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