Goodwill and Intangible Assets, net (Schedule of Goodwill) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Goodwill [Line Items]
As of December 31, 2017	$ 1,003
Acquisitions (Note 3)	84
Exchange rate changes	(23)
As of June 30, 2017	1,064	[1]
Goodwill, Impaired, Accumulated Impairment Loss	0
Engineered Materials [Member]
Goodwill [Line Items]
As of December 31, 2017	643
Acquisitions (Note 3)	84
Exchange rate changes	(16)
As of June 30, 2017	711	[1]
Consumer Specialties [Member]
Goodwill [Line Items]
As of December 31, 2017	149
Acquisitions (Note 3)	0
Exchange rate changes	0
As of June 30, 2017	149	[1]
Industrial Specialties [Member]
Goodwill [Line Items]
As of December 31, 2017	40
Acquisitions (Note 3)	0
Exchange rate changes	(1)
As of June 30, 2017	39	[1]
Acetyl Intermediates [Member]
Goodwill [Line Items]
As of December 31, 2017	171
Acquisitions (Note 3)	0
Exchange rate changes	(6)
As of June 30, 2017	$ 165	[1]

[1] There were $0 million of accumulated impairment losses as of September 30, 2018.