Consolidating Guarantor Financial Information (Schedule of Consolidating Statement of Operations) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Condensed Financial Statements, Captions [Line Items]
Net sales	$ 1,477	$ 1,769	$ 2,927	$ 3,474
Cost of Goods and Services Sold	(1,102)	(1,361)	(2,171)	(2,688)
Gross Profit	375	408	756	786
Selling, General and Administrative Expense	(106)	(119)	(204)	(223)
Amortization of Intangible Assets	(3)	(5)	(6)	(11)
Research and Development Expense	(59)	(24)	(79)	(46)
Other (Charges) Gains, Net	(10)	2	(15)	1
Foreign exchange gain (loss), net	(3)	(1)	0	(2)
Gain (loss) on disposition of businesses and assets, net	(6)	(2)	(7)	(3)
Operating Income (Loss)	188	259	445	502
Equity in net earnings (loss) of affiliates	40	101	88	141
Interest Expense	(30)	(40)	(57)	(79)
Interest income	1	2	1	2
Dividend income - cost investments	26	29	54	58
Other income (expense), net	2	1	2	1
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	227	352	533	625
Income Tax Expense (Benefit)	(24)	(94)	(96)	(172)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	203	258	437	453
Earnings (loss) from operation of discontinued operations	(3)	(1)	(3)	(1)
Discontinued Operation, Tax Effect of Discontinued Operation	1	1	1	1
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(2)	0	(2)	0
Net earnings (loss)	201	258	435	453
Net Income (Loss) Attributable to Noncontrolling Interest	4	1	6	2
Net earnings (loss) attributable to Celanese Corporation	205	259	441	455
Parent Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales	0	0	0	0
Cost of Goods and Services Sold	0	0	0	0
Gross Profit	0	0	0	0
Selling, General and Administrative Expense	0	0	0	0
Amortization of Intangible Assets	0	0	0	0
Research and Development Expense	0	0	0	0
Other (Charges) Gains, Net	0	0	0	0
Foreign exchange gain (loss), net	0	0	0	0
Gain (loss) on disposition of businesses and assets, net	0	0	0	0
Operating Income (Loss)	0	0	0	0
Equity in net earnings (loss) of affiliates	206	259	441	454
Interest Expense	0	0	0	0
Interest income	0	0	0	0
Dividend income - cost investments	0	0	0	0
Other income (expense), net	0	0	0	0
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	206	259	441	454
Income Tax Expense (Benefit)	(1)	0	0	1
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	205	259	441	455
Earnings (loss) from operation of discontinued operations	0	0	0	0
Discontinued Operation, Tax Effect of Discontinued Operation	0	0	0	0
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss)	205	259	441	455
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss) attributable to Celanese Corporation	205	259	441	455
Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales	0	0	0	0
Cost of Goods and Services Sold	0	0	0	0
Gross Profit	0	0	0	0
Selling, General and Administrative Expense	0	0	0	0
Amortization of Intangible Assets	0	0	0	0
Research and Development Expense	0	0	0	0
Other (Charges) Gains, Net	0	0	0	0
Foreign exchange gain (loss), net	0	0	0	0
Gain (loss) on disposition of businesses and assets, net	0	0	0	0
Operating Income (Loss)	0	0	0	0
Equity in net earnings (loss) of affiliates	244	282	523	510
Interest Expense	(41)	(49)	(84)	(95)
Interest income	5	17	13	31
Dividend income - cost investments	0	0	0	0
Other income (expense), net	0	0	0	0
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	208	250	452	446
Income Tax Expense (Benefit)	(2)	9	(11)	8
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	206	259	441	454
Earnings (loss) from operation of discontinued operations	0	0	0	0
Discontinued Operation, Tax Effect of Discontinued Operation	0	0	0	0
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss)	206	259	441	454
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss) attributable to Celanese Corporation	206	259	441	454
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales	674	679	1,332	1,386
Cost of Goods and Services Sold	(474)	(501)	(905)	(962)
Gross Profit	200	178	427	424
Selling, General and Administrative Expense	(29)	(18)	(53)	(27)
Amortization of Intangible Assets	(2)	(2)	(3)	(4)
Research and Development Expense	(49)	(13)	(59)	(26)
Other (Charges) Gains, Net	0	0	(3)	0
Foreign exchange gain (loss), net	0	0	0	0
Gain (loss) on disposition of businesses and assets, net	(1)	(2)	(3)	(5)
Operating Income (Loss)	119	143	306	362
Equity in net earnings (loss) of affiliates	114	48	206	78
Interest Expense	(8)	(6)	(13)	(12)
Interest income	20	18	39	35
Dividend income - cost investments	0	0	0	0
Other income (expense), net	1	1	1	4
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	246	204	539	467
Income Tax Expense (Benefit)	(29)	(52)	(82)	(122)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	217	152	457	345
Earnings (loss) from operation of discontinued operations	(3)	(1)	(3)	(1)
Discontinued Operation, Tax Effect of Discontinued Operation	1	1	1	1
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(2)	0	(2)	0
Net earnings (loss)	215	152	455	345
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss) attributable to Celanese Corporation	215	152	455	345
Non-Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales	1,174	1,357	2,307	2,657
Cost of Goods and Services Sold	(1,011)	(1,149)	(1,995)	(2,300)
Gross Profit	163	208	312	357
Selling, General and Administrative Expense	(77)	(101)	(151)	(196)
Amortization of Intangible Assets	(1)	(3)	(3)	(7)
Research and Development Expense	(10)	(11)	(20)	(20)
Other (Charges) Gains, Net	(10)	2	(12)	1
Foreign exchange gain (loss), net	(3)	(1)	0	(2)
Gain (loss) on disposition of businesses and assets, net	(5)	0	(4)	2
Operating Income (Loss)	57	94	122	135
Equity in net earnings (loss) of affiliates	35	89	75	125
Interest Expense	(8)	(21)	(20)	(40)
Interest income	3	3	9	4
Dividend income - cost investments	26	29	54	58
Other income (expense), net	1	0	1	(3)
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	114	194	241	279
Income Tax Expense (Benefit)	9	(46)	(1)	(57)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	123	148	240	222
Earnings (loss) from operation of discontinued operations	0	0	0	0
Discontinued Operation, Tax Effect of Discontinued Operation	0	0	0	0
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss)	123	148	240	222
Net Income (Loss) Attributable to Noncontrolling Interest	4	1	6	2
Net earnings (loss) attributable to Celanese Corporation	127	149	246	224
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales	(371)	(267)	(712)	(569)
Cost of Goods and Services Sold	383	289	729	574
Gross Profit	12	22	17	5
Selling, General and Administrative Expense	0	0	0	0
Amortization of Intangible Assets	0	0	0	0
Research and Development Expense	0	0	0	0
Other (Charges) Gains, Net	0	0	0	0
Foreign exchange gain (loss), net	0	0	0	0
Gain (loss) on disposition of businesses and assets, net	0	0	0	0
Operating Income (Loss)	12	22	17	5
Equity in net earnings (loss) of affiliates	(559)	(577)	(1,157)	(1,026)
Interest Expense	27	36	60	68
Interest income	(27)	(36)	(60)	(68)
Dividend income - cost investments	0	0	0	0
Other income (expense), net	0	0	0	0
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	(547)	(555)	(1,140)	(1,021)
Income Tax Expense (Benefit)	(1)	(5)	(2)	(2)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	(548)	(560)	(1,142)	(1,023)
Earnings (loss) from operation of discontinued operations	0	0	0	0
Discontinued Operation, Tax Effect of Discontinued Operation	0	0	0	0
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss)	(548)	(560)	(1,142)	(1,023)
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net earnings (loss) attributable to Celanese Corporation	$ (548)	$ (560)	$ (1,142)	$ (1,023)