Revenue Recognition - Disaggregation of net sales (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2019		Jun. 30, 2018		Jun. 30, 2019		Jun. 30, 2018
Revenue, Major Customer [Line Items]
Net sales		$ 1,592		$ 1,844		$ 3,279		$ 3,695
Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales	[1]	835		1,018		1,693		2,036
Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		593		664		1,256		1,329
Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		164		162		330		330
Intersegment Eliminations [Member]
Revenue, Major Customer [Line Items]
Net sales		(30)	[2]	(31)	[2]	(61)	[3]	(64)	[3]
Intersegment Eliminations [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		30		31		61		64
North America [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		278		285		564		575
North America [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		180		191		376		370
North America [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		33		33		67		68
Europe and Africa [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		282		339		576		656
Europe and Africa [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		269		331		571		668
Europe and Africa [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		67		48		130		118
Asia Pacific [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		252		362		508		740
Asia Pacific [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		126		126		274		258
Asia Pacific [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		56		68		116		119
South America [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		23		32		45		65
South America [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		18		16		35		33
South America [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		$ 8		$ 13		$ 17		$ 25

[1] Excludes intersegment sales of $30 million and $31 million for the three months ended June 30, 2019 and 2018, respectively. Excludes intersegment sales of $61 million and $64 million for the six months ended June 30, 2019 and 2018, respectively.

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

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