Segment Information (Schedule of Business Segments) (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2021		Jun. 30, 2020		Jun. 30, 2021		Jun. 30, 2020		Dec. 31, 2020
Segment Reporting Information [Line Items]
Net sales		$ 2,198		$ 1,193		$ 3,996		$ 2,653
Other (charges) gains, net (Note 14)		(3)		(21)		3		(27)
Operating profit (loss)		567		83		893		277
Equity in net earnings (loss) of affiliates		37		31		66		88
Depreciation and amortization		91		87		181		172
Capital expenditures		113	[1]	80	[1]	186	[2]	166	[2]
Goodwill and intangible assets, net		1,447				1,447				$ 1,485
Total assets		11,220				11,220				10,909
Increase (decrease) in accrued capital expenditures		3		(8)		(16)		(41)
Acetate Tow
Segment Reporting Information [Line Items]
Net sales		138		127		257		256
Acetyl Chain
Segment Reporting Information [Line Items]
Net sales	[3]	1,378		646		2,412		1,414
Engineered Materials
Segment Reporting Information [Line Items]
Net sales		682		420		1,327		983
Operating Segments [Member] | Acetate Tow
Segment Reporting Information [Line Items]
Net sales		138		127		257		256
Other (charges) gains, net (Note 14)		0		0		0		(1)
Operating profit (loss)		24		31		40		58
Equity in net earnings (loss) of affiliates		0		0		0		0
Depreciation and amortization		9		9		19		17
Capital expenditures		10		6		21		16
Goodwill and intangible assets, net		154				154				154
Total assets		1,057				1,057				975
Operating Segments [Member] | Acetyl Chain
Segment Reporting Information [Line Items]
Net sales		1,409		662		2,465		1,461
Other (charges) gains, net (Note 14)		0		5		0		5
Operating profit (loss)		516		121		767		256
Equity in net earnings (loss) of affiliates		2		0		4		1
Depreciation and amortization		43		42		84		81
Capital expenditures		65		38		98		81
Goodwill and intangible assets, net		291				291				301
Total assets		4,461				4,461				3,930
Operating Segments [Member] | Engineered Materials
Segment Reporting Information [Line Items]
Net sales		682		420		1,327		983
Other (charges) gains, net (Note 14)		(1)		(25)		6		(25)
Operating profit (loss)		123		(13)		253		89
Equity in net earnings (loss) of affiliates		32		26		57		79
Depreciation and amortization		35		32		70		66
Capital expenditures		33		28		56		52
Goodwill and intangible assets, net		1,002				1,002				1,030
Total assets		4,138				4,138				3,990
Corporate, Non-Segment [Member] | Other
Segment Reporting Information [Line Items]
Net sales		0		0		0		0
Other (charges) gains, net (Note 14)		(2)		(1)		(3)		(6)
Operating profit (loss)		(96)		(56)		(167)		(126)
Equity in net earnings (loss) of affiliates		3		5		5		8
Depreciation and amortization		4		4		8		8
Capital expenditures		5		8		11		17
Goodwill and intangible assets, net		0				0				0
Total assets		1,564				1,564				2,014
Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales		(31)	[4]	(16)	[4]	(53)	[5]	(47)	[5]
Other (charges) gains, net (Note 14)		0		0		0		0
Operating profit (loss)		0		0		0		0
Equity in net earnings (loss) of affiliates		0		0		0		0
Depreciation and amortization		0		0		0		0
Capital expenditures		0		0		0		0
Goodwill and intangible assets, net		0				0				0
Total assets		0				0				$ 0
Eliminations [Member] | Acetyl Chain
Segment Reporting Information [Line Items]
Net sales		$ 31		$ 16		$ 53		$ 47

[1] Includes an increase in accrued capital expenditures of $3 million and a decrease of $8 million for the three months ended June 30, 2021 and 2020, respectively.

[2] Includes a decrease in accrued capital expenditures of $16 million and $41 million for the six months ended June 30, 2021 and 2020, respectively.

[3] Excludes intersegment sales of $31 million and $16 million for the three months ended June 30, 2021 and 2020, respectively. Excludes intersegment sales of $53 million and $47 million for the six months ended June 30, 2021 and 2020, respectively.

[4] Includes intersegment sales primarily related to the Acetyl Chain.

[5] Includes intersegment sales primarily related to the Acetyl Chain.