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Acquisitions, Dispositions and Plant Closures Plant Closures - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Sep. 30, 2023	Mar. 31, 2024	Mar. 31, 2023
Restructuring Cost and Reserve [Line Items]
Proceeds from sale of businesses and assets, net		$ 0	$ 9
Gain (loss) on disposition of businesses and assets, net		(1)	$ 5
Uentrop, Germany \| Engineered Materials
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost		36
Mechelen, Belgium \| Engineered Materials
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost		$ 130
Nutrinova Joint Venture
Restructuring Cost and Reserve [Line Items]
Gain (loss) on disposition of businesses and assets, net	$ 515
Celanese Corporation \| Nutrinova Joint Venture
Restructuring Cost and Reserve [Line Items]
Equity method investment, ownership percentage	30.00%
Mitsui & Co. Ltd. \| Nutrinova Joint Venture
Restructuring Cost and Reserve [Line Items]
Equity method investment, ownership percentage	70.00%
Proceeds from sale of businesses and assets, net	$ 503