Goodwill and Intangible Assets, Net (Schedule of Goodwill) (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended		12 Months Ended
		Dec. 31, 2024	Sep. 30, 2024		Dec. 31, 2024		Dec. 31, 2023
Goodwill
Goodwill, beginning balance			$ 6,977,000	[1]	$ 6,977,000	[1]	$ 7,142,000
Acquisitions							(107,000)
Dispositions							(80,000)
Impairment losses			0		(1,517,000)
Exchange rate changes					(73,000)		22,000
Goodwill, ending balance	[1]	$ 5,387,000			5,387,000		6,977,000
Accumulated impairment losses							0
Engineered Materials
Goodwill
Goodwill, beginning balance			6,602,000	[1]	6,602,000	[1]	6,775,000
Acquisitions							(107,000)
Dispositions							(80,000)
Impairment losses		1,500,000			(1,517,000)
Exchange rate changes					(60,000)		14,000
Goodwill, ending balance	[1]	5,025,000			5,025,000		6,602,000
Accumulated impairment losses		(1,500,000)			(1,500,000)
Acetyl Chain
Goodwill
Goodwill, beginning balance			$ 375,000	[1]	375,000	[1]	367,000
Acquisitions							0
Dispositions							0
Impairment losses					0
Exchange rate changes					(13,000)		8,000
Goodwill, ending balance	[1]	$ 362,000			$ 362,000		$ 375,000

[1] Includes accumulated impairment losses of $1.5 billion in the Engineered Materials segment as of December 31, 2024. There were no accumulated impairment losses as of December 31, 2023.