Consolidated Statements of Operations - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Net sales	$ 7,155	$ 6,140	$ 5,389
Cost of sales	(5,183)	(4,629)	(3,984)
Gross profit	1,972	1,511	1,405
Selling, general and administrative expenses	(546)	(496)	(378)
Amortization of intangible assets	(24)	(20)	(9)
Research and development expenses	(72)	(73)	(78)
Other (charges) gains, net	9	(59)	(8)
Foreign exchange gain (loss), net	0	(1)	(1)
Gain (loss) on disposition of businesses and assets, net	(5)	(5)	3
Operating profit (loss)	1,334	857	934
Equity in net earnings (loss) of affiliates	233	183	155
Non-operating pension and other postretirement employee benefit (expense) income	(62)	44	(41)
Interest expense	(125)	(122)	(120)
Refinancing expense	(1)	0	(6)
Interest income	6	2	2
Dividend income - equity investments	117	108	108
Other income (expense), net	8	3	(2)
Earnings (loss) from continuing operations before tax	1,510	1,075	1,030
Income tax (provision) benefit	(292)	(213)	(122)
Earnings (loss) from continuing operations	1,218	862	908
Earnings (loss) from operation of discontinued operations	(5)	(16)	(3)
Gain (loss) on disposition of discontinued operations	0	0	0
Income tax (provision) benefit from discontinued operations	0	3	1
Earnings (loss) from discontinued operations	(5)	(13)	(2)
Net earnings (loss)	1,213	849	906
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	6	6	6
Net (earnings) loss attributable to noncontrolling interests	(6)	(6)	(6)
Net earnings (loss) attributable to Celanese Corporation	1,207	843	900
Amounts attributable to Celanese Corporation
Earnings (loss) from continuing operations	1,212	856	902
Earnings (loss) from discontinued operations	(5)	(13)	(2)
Net earnings (loss) attributable to Celanese Corporation	$ 1,207	$ 843	$ 900
Earnings (loss) per common share - basic
Continuing operations	$ 9.03	$ 6.21	$ 6.22
Discontinued operations	(0.04)	(0.10)	(0.01)
Net earnings (loss) - basic	8.99	6.11	6.21
Earnings (loss) per common share - diluted
Continuing operations	8.95	6.19	6.19
Discontinued operations	(0.04)	(0.10)	(0.01)
Net earnings (loss) - diluted	$ 8.91	$ 6.09	$ 6.18
Weighted average shares - basic	134,305,269	137,902,667	144,939,433
Weighted average shares - diluted	135,416,858	138,317,395	145,668,181