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

No definition available.

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Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Subparagraph (SX 210.5-02(22)(a)(1))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Period Type:	instant

- 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.

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Balance Type:	debit
Period Type:	instant

- 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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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+ Details

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- Details

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- Details

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- Details

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- Details

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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