Fair Value Measurements - Schedule of Carrying Values and Estimated Fair Values of Financial Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 508,237	$ 503,946
Long-term debt, fair value	517,310	503,805
Finance lease obligations	$ 6,668	$ 2,636
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 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 49,929	$ 49,926
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 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 99,584	$ 99,565
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 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 294,600	$ 294,523
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 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	60,000	60,000
Subtotal long-term debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	517,310	503,805
Subtotal long-term debt \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	504,113	504,014
Unamortized debt issuance costs \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt issuance costs	$ (2,544)	$ (2,704)

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

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

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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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