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Fair Value Measurements - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Fair Value Measurements - Narrative (Details) - USD ($)	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Jan. 31, 2026	Dec. 31, 2025	Sep. 30, 2024	Mar. 31, 2024	Oct. 31, 2021	Mar. 31, 2021	Apr. 30, 2019
Fair Value Measurements
Contribution to decommissioning trust fund			$ 11,600,000	$ 11,500,000
Impairment of long-lived assets	$ 0	$ 0	$ 0	$ 0
7.125% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)											7.125%
7.750% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)									7.75%
7.500% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)										7.50%
8.750% Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)							8.75%
3.125% Convertible Senior Notes \| Senior Notes
Fair Value Measurements
Interest rate (as a percent)	3.125%		3.125%			3.125%		3.125%
11.250% Senior Secured Bonds \| Senior Secured Bond
Fair Value Measurements
Interest rate (as a percent)					11.25%