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Commitments and Contingencies (Additional Information) (Details) $ in Thousands, € in Millions, R$ in Millions	1 Months Ended					6 Months Ended
	Jul. 31, 2025 USD ($)	Nov. 30, 2024 USD ($)	May 31, 2024 BRL (R$)	Mar. 31, 2022 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2026 EUR (€)	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
Environmental Loss Contingencies [Line Items]
Environmental contingency accrual						$ 66,000			$ 69,000
Minimum
Environmental Loss Contingencies [Line Items]
Environmental exit costs, reasonably possible additional loss						100,000
Maximum
Environmental Loss Contingencies [Line Items]
Environmental exit costs, reasonably possible additional loss						170,000
Antitrust Proceedings
Environmental Loss Contingencies [Line Items]
Damages sought	$ 80,000
Litigation Settlement, Amount Awarded to Other Party						350
Antitrust Proceedings \| Direct Purchasers \| Settled Litigation
Environmental Loss Contingencies [Line Items]
Damages sought					$ 861,000
Antitrust Proceedings \| Indirect Purchasers \| Settled Litigation
Environmental Loss Contingencies [Line Items]
Damages sought					$ 500,000
Ethylene Antitrust Litigation Proceedings \| Pending Litigation
Environmental Loss Contingencies [Line Items]
Damages sought \| €							€ 11,203
Ethylene Antitrust Litigation Proceedings \| Dismissed Litigation
Environmental Loss Contingencies [Line Items]
Damages sought \| €							€ 1,025
PVC Pipe Antitrust
Environmental Loss Contingencies [Line Items]
Loss contingency accrual								$ 67,000
Brazilian Contractual Indemnification Lawsuit
Environmental Loss Contingencies [Line Items]
Damages awarded \| R$			R$ 550
Legal fee and procedural fine percent			20.00%
Calvert City Proceedings
Environmental Loss Contingencies [Line Items]
Damages sought				$ 39,000
Sulphur Brine Dome
Environmental Loss Contingencies [Line Items]
Damages sought		$ 100,000
Loss contingency accrual						$ 22,000