Other (Charges) Gains, Net - Schedule of Restructuring Reserve by Type of Cost (Details) - Employee Severance $ in Millions	3 Months Ended
	Mar. 31, 2026 USD ($)
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	$ 31
Additions	20
Cash payments	(17)
Reserve as of the end of the period	34
Engineered Materials
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	14
Additions	7
Cash payments	(12)
Reserve as of the end of the period	9
Acetyl Chain
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	9
Additions	9
Cash payments	(1)
Reserve as of the end of the period	17
Other
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	8
Additions	4
Cash payments	(4)
Reserve as of the end of the period	$ 8