Other (Charges) Gains, Net (Schedule of Other (Charges) Gains, Net) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring Reserve	$ 16		$ 16
Restructuring Cost and Reserve [Line Items]
Restructuring	(6)	$ (1)	(20)	$ (4)
Asset impairments	0	0	(83)	0
Other plant/office closures	(1)	13	(2)	13
Commercial disputes	0	0	4	0
Other (charges) gains, net	(7)	$ 12	(101)	$ 9
Restructuring Reserve	16		16
Engineered Materials [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	5		5
Restructuring Cost and Reserve [Line Items]
Commercial disputes			15
Restructuring Reserve	5		5
Acetate Tow [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	4		4
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	4		4
Acetyl Chain [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	2		2
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	2		2
Other Activities [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	5		5
Restructuring Cost and Reserve [Line Items]
Commercial disputes			11
Restructuring Reserve	5		5
Employee Severance [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	15		15		$ 4
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			21
Payments for Restructuring			(9)
Restructuring Reserve, Accrual Adjustment			1
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	15		15		4
Employee Severance [Member] | Engineered Materials [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	5		5		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			9
Payments for Restructuring			4
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	5		5		0
Employee Severance [Member] | Acetate Tow [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	3		3		2
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			3
Payments for Restructuring			2
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	3		3		2
Employee Severance [Member] | Acetyl Chain [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	2		2		2
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			1
Payments for Restructuring			0
Restructuring Reserve, Accrual Adjustment			1
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	2		2		2
Employee Severance [Member] | Other Activities [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	5		5		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			8
Payments for Restructuring			3
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	5		5		0
Facility Closing [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	1		1		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			1
Payments for Restructuring			0
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	1		1		0
Facility Closing [Member] | Engineered Materials [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	0		0		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0
Payments for Restructuring			0
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	0		0		0
Facility Closing [Member] | Acetate Tow [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	1		1		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			1
Payments for Restructuring			0
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	1		1		0
Facility Closing [Member] | Acetyl Chain [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	0		0		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0
Payments for Restructuring			0
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	0		0		0
Facility Closing [Member] | Other Activities [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	0		0		0
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0
Payments for Restructuring			0
Restructuring Reserve, Accrual Adjustment			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Restructuring Reserve	$ 0		$ 0		$ 0