Fair-Value Measurements (Narrative) (Details) $ in Thousands	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Senior unsecured notes	$ 3,436,860	$ 3,062,955
Principal	4,189,987	3,823,215
5.875% Alkali senior secured notes due 2042
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Principal	400,000
Senior Unsecured Notes
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of debt	3,500,000	3,200,000
Principal	$ 3,500,000	$ 3,100,000
Measurement Input, Equity Volatility
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Embedded derivative feature			50