Other (Charges) Gains, Net (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring Cost and Reserve [Line Items]
Other plant/office closures	$ 0	$ (3)	$ 0	$ 50
Employee termination benefits	$ (3)	(1)	$ (3)	$ (3)
Acetyl Intermediates [Member]
Restructuring Cost and Reserve [Line Items]
Other plant/office closures		50
Acetyl Intermediates [Member] | Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Other plant/office closures		24
Acetyl Intermediates [Member] | Non-income tax receivable adjustment [Member]
Restructuring Cost and Reserve [Line Items]
Other plant/office closures		$ 18