Revenue Disaggregated Revenue (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net sales		$ 7,155	$ 6,140	$ 5,389
Intersegment [Member]
Disaggregation of Revenue [Line Items]
Net sales		(129)	(112)	(116)
Engineered Materials [Member]
Disaggregation of Revenue [Line Items]
Net sales		2,593
Acetate Tow [Member]
Disaggregation of Revenue [Line Items]
Net sales		649
Acetate Tow [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Net sales		0	2	0
Acetyl Chain [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	3,913
Acetyl Chain [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Net sales		129	$ 110	$ 116
North America [Member] | Engineered Materials [Member]
Disaggregation of Revenue [Line Items]
Net sales		770
North America [Member] | Acetate Tow [Member]
Disaggregation of Revenue [Line Items]
Net sales		133
North America [Member] | Acetyl Chain [Member]
Disaggregation of Revenue [Line Items]
Net sales		1,145
Europe and Africa | Engineered Materials [Member]
Disaggregation of Revenue [Line Items]
Net sales		1,216
Europe and Africa | Acetate Tow [Member]
Disaggregation of Revenue [Line Items]
Net sales		260
Europe and Africa | Acetyl Chain [Member]
Disaggregation of Revenue [Line Items]
Net sales		1,236
Asia Pacific [Member] | Engineered Materials [Member]
Disaggregation of Revenue [Line Items]
Net sales		532
Asia Pacific [Member] | Acetate Tow [Member]
Disaggregation of Revenue [Line Items]
Net sales		217
Asia Pacific [Member] | Acetyl Chain [Member]
Disaggregation of Revenue [Line Items]
Net sales		1,411
South America [Member] | Engineered Materials [Member]
Disaggregation of Revenue [Line Items]
Net sales		75
South America [Member] | Acetate Tow [Member]
Disaggregation of Revenue [Line Items]
Net sales		39
South America [Member] | Acetyl Chain [Member]
Disaggregation of Revenue [Line Items]
Net sales		$ 121

[1] Excludes intersegment sales of $129 million for the year ended December 31, 2018.