Other (Charges) Gains, Net - Schedule of Restructuring Reserve by Type of Cost (Details) - Employee Severance $ in Millions	9 Months Ended
	Sep. 30, 2025 USD ($)
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	$ 63
Additions	56
Cash payments	(93)
Other changes	0
Exchange rate changes	3
Reserve as of the end of the period	29
Engineered Materials
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	57
Additions	35
Cash payments	(73)
Other changes	(4)
Exchange rate changes	2
Reserve as of the end of the period	17
Acetyl Chain [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0
Additions	4
Cash payments	(2)
Other changes	0
Exchange rate changes	0
Reserve as of the end of the period	2
Corporate Segment and Other Operating Segment [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	6
Additions	17
Cash payments	(18)
Other changes	4
Exchange rate changes	1
Reserve as of the end of the period	$ 10