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Fair Value Measurements - Schedule of Carrying Values and Estimated Fair Values of Financial Liabilities (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt | $ 508,801 | $ 503,946
Long-term debt, fair value | 491,369 | 503,805
Finance lease obligations | $ 7,318 | $ 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 | $ 51,301 | $ 53,047
7.25% Senior Notes | Carrying Amount |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt | $ 49,928 | $ 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 | $ 99,393 | $ 104,039
6.70% Senior Notes | Carrying Amount |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt | $ 99,577 | $ 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 | $ 283,037 | $ 288,787
5.375% Senior Notes | Carrying Amount |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt | $ 294,574 | $ 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 | $ 57,638 | $ 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 | 491,369 | 503,805
Subtotal long-term debt | Carrying Amount |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt | 504,079 | 504,014
Unamortized debt issuance costs | Carrying Amount |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Unamortized debt issuance costs | $ (2,596) | $ (2,704)

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