Revenue Recognition - Disaggregation of net sales (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2019		Sep. 30, 2018		Sep. 30, 2019		Sep. 30, 2018
Revenue, Major Customer [Line Items]
Net sales		$ 1,586		$ 1,771		$ 4,865		$ 5,466
Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales	[1]	837		971		2,530		3,007
Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		591		642		1,847		1,971
Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		158		158		488		488
Intersegment Eliminations [Member]
Revenue, Major Customer [Line Items]
Net sales		(30)	[2]	(35)	[2]	(91)	[3]	(99)	[3]
Intersegment Eliminations [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		30		35		91		99
North America [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		273		298		837		873
North America [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		195		197		571		567
North America [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		30		30		97		98
Europe and Africa [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		280		302		856		958
Europe and Africa [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		251		277		822		945
Europe and Africa [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		63		78		193		196
Asia Pacific [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		264		341		772		1,081
Asia Pacific [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		126		145		400		403
Asia Pacific [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		60		44		176		163
South America [Member] | Acetyl Chain [Member]
Revenue, Major Customer [Line Items]
Net sales		20		30		65		95
South America [Member] | Engineered Materials [Member]
Revenue, Major Customer [Line Items]
Net sales		19		23		54		56
South America [Member] | Acetate Tow [Member]
Revenue, Major Customer [Line Items]
Net sales		$ 5		$ 6		$ 22		$ 31

[1] Excludes intersegment sales of $30 million and $35 million for the three months ended September 30, 2019 and 2018, respectively. Excludes intersegment sales of $91 million and $99 million for the nine months ended September 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.