Unaudited Interim Consolidated Statement Equity - 6 months ended Jun. 30, 2017 - USD ($) $ in Millions	Total	Series A Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Balance as of the beginning of the period, shares at Dec. 31, 2016		140,660,447	26,950,910
Balance as of the beginning of the period at Dec. 31, 2016	$ 3,021
Total Celanese Corporation stockholders' equity at Dec. 31, 2016	$ 2,588	$ 0	$ (1,531)	$ 157	$ 4,320	$ (358)
Stock option exercises, shares		16,151
Stock option exercises, net of tax		$ 0		1
Purchases of treasury stock, shares		(3,412,858)
Purchases of treasury stock, including related fees		$ 0
Stock awards, shares		391,027
Stock awards		$ 0
Purchases of treasury stock, shares	3,412,858		3,412,858
Purchases of treasury stock, including related fees	$ (303)		$ (303)
Stock-based compensation, net of tax				0
Cumulative effect adjustment from adoption of new accounting standard (Note 1)					(1)
Net earnings (loss) attributable to Celanese Corporation	414				414
Series A common stock dividends					(116)
Other comprehensive income (loss), net of tax	111					111
Balance as of the end of the period, shares at Jun. 30, 2017		137,654,767	30,363,768
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2016	433						$ 433
Net earnings (loss) attributable to noncontrolling interests	3						3
(Distributions to) contributions from noncontrolling interests							(8)
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2017	428						$ 428
Total Celanese Corporation stockholders' equity at Jun. 30, 2017	2,694	$ 0	$ (1,834)	$ 158	$ 4,617	$ (247)
Balance as of the end of the period at Jun. 30, 2017	$ 3,122