Fair Value Measurements - Schedule of Carrying Values and Estimated Fair Values of Financial Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 901,519	$ 901,873
Unamortized debt issuance costs	(5,389)	(5,904)
Finance lease obligations	2,583	3,570
Fair Value	854,835	924,252
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 904,325	$ 904,207
3.03% borrowings from FHLBI
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate	3.03%	3.03%
Fair Value	$ 59,816	$ 59,625
3.03% borrowings from FHLBI \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 60,000	$ 60,000
Senior Notes \| 7.25% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate	7.25%	7.25%
Fair Value	$ 52,934	$ 56,973
Senior Notes \| 7.25% Senior Notes \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 49,940	$ 49,936
Senior Notes \| 6.70% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate	6.70%	6.70%
Fair Value	$ 101,158	$ 110,244
Senior Notes \| 6.70% Senior Notes \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 99,638	$ 99,617
Senior Notes \| 5.90% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate	5.90%	5.90%
Fair Value	$ 389,612	$ 419,869
Senior Notes \| 5.90% Senior Notes \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 399,923	$ 399,917
Senior Notes \| 5.375% Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate	5.375%	5.375%
Fair Value	$ 251,315	$ 277,541
Senior Notes \| 5.375% Senior Notes \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying Amount	$ 294,824	$ 294,737

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

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