Consolidating Guarantor Financial Information (Schedule of Consolidating Balance Sheet) (Details) - USD ($) $ in Millions	Sep. 30, 2017		Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Current Assets
Cash and cash equivalents	$ 461		$ 638	$ 1,252	$ 967
Trade receivables - third party and affiliates	989		801
Non-trade receivables, net	260		223
Inventories, net	809		720
Marketable securities, at fair value	31		30
Other assets	63		60
Total current assets	2,613		2,472
Investments in affiliates	938		852
Property, Plant and Equipment, Net	3,706		3,577
Deferred income taxes	201		159
Other assets	306		307
Goodwill	995	[1]	796
Intangible Assets, Net (Excluding Goodwill)	303		194
Total assets	9,062		8,357
Current Liabilities
Short-term borrowings and current installments of long-term debt - third party and affiliates	435		118
Trade payables - third party and affiliates	695		625
Other liabilities	343		322
Income taxes payable	77		12
Total current liabilities	1,550		1,077
Noncurrent Liabilities
Long-term debt, net of unamortized deferred financing costs	2,954		2,890
Deferred income taxes	195		130
Uncertain tax positions	153		131
Benefit obligations	845		893
Other liabilities	230		215
Total noncurrent liabilities	4,377		4,259
Total Celanese Corporation stockholders' equity	2,715		2,588
Noncontrolling interests	420		433
Total equity	3,135		3,021
Total liabilities and equity	9,062		8,357
Parent Guarantor [Member]
Current Assets
Cash and cash equivalents	0		0	0	0
Trade receivables - third party and affiliates	0		0
Non-trade receivables, net	40		40
Inventories, net	0		0
Marketable securities, at fair value	0		0
Other assets	0		0
Total current assets	40		40
Investments in affiliates	2,675		2,548
Property, Plant and Equipment, Net	0		0
Deferred income taxes	0		0
Other assets	0		0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Total assets	2,715		2,588
Current Liabilities
Short-term borrowings and current installments of long-term debt - third party and affiliates	0		0
Trade payables - third party and affiliates	0		0
Other liabilities	0		0
Income taxes payable	0		0
Total current liabilities	0		0
Noncurrent Liabilities
Long-term debt, net of unamortized deferred financing costs	0		0
Deferred income taxes	0		0
Uncertain tax positions	0		0
Benefit obligations	0		0
Other liabilities	0		0
Total noncurrent liabilities	0		0
Total Celanese Corporation stockholders' equity	2,715		2,588
Noncontrolling interests	0		0
Total equity	2,715		2,588
Total liabilities and equity	2,715		2,588
Issuer [Member]
Current Assets
Cash and cash equivalents	5		0	2	0
Trade receivables - third party and affiliates	0		0
Non-trade receivables, net	513		499
Inventories, net	0		0
Marketable securities, at fair value	0		0
Other assets	51		42
Total current assets	569		541
Investments in affiliates	4,317		4,029
Property, Plant and Equipment, Net	0		0
Deferred income taxes	2		0
Other assets	878		705
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Total assets	5,766		5,275
Current Liabilities
Short-term borrowings and current installments of long-term debt - third party and affiliates	245		6
Trade payables - third party and affiliates	0		0
Other liabilities	82		58
Income taxes payable	0		0
Total current liabilities	327		64
Noncurrent Liabilities
Long-term debt, net of unamortized deferred financing costs	2,764		2,647
Deferred income taxes	0		16
Uncertain tax positions	0		0
Benefit obligations	0		0
Other liabilities	0		0
Total noncurrent liabilities	2,764		2,663
Total Celanese Corporation stockholders' equity	2,675		2,548
Noncontrolling interests	0		0
Total equity	2,675		2,548
Total liabilities and equity	5,766		5,275
Subsidiary Guarantors [Member]
Current Assets
Cash and cash equivalents	70		51	652	21
Trade receivables - third party and affiliates	134		107
Non-trade receivables, net	230		249
Inventories, net	246		239
Marketable securities, at fair value	31		30
Other assets	14		25
Total current assets	725		701
Investments in affiliates	3,977		3,655
Property, Plant and Equipment, Net	1,106		1,049
Deferred income taxes	103		91
Other assets	120		133
Goodwill	314		314
Intangible Assets, Net (Excluding Goodwill)	49		48
Total assets	6,394		5,991
Current Liabilities
Short-term borrowings and current installments of long-term debt - third party and affiliates	138		133
Trade payables - third party and affiliates	261		226
Other liabilities	241		167
Income taxes payable	574		454
Total current liabilities	1,214		980
Noncurrent Liabilities
Long-term debt, net of unamortized deferred financing costs	899		727
Deferred income taxes	16		0
Uncertain tax positions	7		3
Benefit obligations	558		636
Other liabilities	58		74
Total noncurrent liabilities	1,538		1,440
Total Celanese Corporation stockholders' equity	3,642		3,571
Noncontrolling interests	0		0
Total equity	3,642		3,571
Total liabilities and equity	6,394		5,991
Non-Guarantors [Member]
Current Assets
Cash and cash equivalents	386		587	598	946
Trade receivables - third party and affiliates	1,004		819
Non-trade receivables, net	412		308
Inventories, net	616		526
Marketable securities, at fair value	0		0
Other assets	104		76
Total current assets	2,522		2,316
Investments in affiliates	826		752
Property, Plant and Equipment, Net	2,600		2,528
Deferred income taxes	98		86
Other assets	169		156
Goodwill	681		482
Intangible Assets, Net (Excluding Goodwill)	254		146
Total assets	7,150		6,466
Current Liabilities
Short-term borrowings and current installments of long-term debt - third party and affiliates	307		250
Trade payables - third party and affiliates	583		524
Other liabilities	285		262
Income taxes payable	24		75
Total current liabilities	1,199		1,111
Noncurrent Liabilities
Long-term debt, net of unamortized deferred financing costs	159		210
Deferred income taxes	181		132
Uncertain tax positions	148		130
Benefit obligations	287		257
Other liabilities	172		142
Total noncurrent liabilities	947		871
Total Celanese Corporation stockholders' equity	4,584		4,051
Noncontrolling interests	420		433
Total equity	5,004		4,484
Total liabilities and equity	7,150		6,466
Eliminations [Member]
Current Assets
Cash and cash equivalents	0		0	$ 0	$ 0
Trade receivables - third party and affiliates	(149)		(125)
Non-trade receivables, net	(935)		(873)
Inventories, net	(53)		(45)
Marketable securities, at fair value	0		0
Other assets	(106)		(83)
Total current assets	(1,243)		(1,126)
Investments in affiliates	(10,857)		(10,132)
Property, Plant and Equipment, Net	0		0
Deferred income taxes	(2)		(18)
Other assets	(861)		(687)
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Total assets	(12,963)		(11,963)
Current Liabilities
Short-term borrowings and current installments of long-term debt - third party and affiliates	(255)		(271)
Trade payables - third party and affiliates	(149)		(125)
Other liabilities	(265)		(165)
Income taxes payable	(521)		(517)
Total current liabilities	(1,190)		(1,078)
Noncurrent Liabilities
Long-term debt, net of unamortized deferred financing costs	(868)		(694)
Deferred income taxes	(2)		(18)
Uncertain tax positions	(2)		(2)
Benefit obligations	0		0
Other liabilities	0		(1)
Total noncurrent liabilities	(872)		(715)
Total Celanese Corporation stockholders' equity	(10,901)		(10,170)
Noncontrolling interests	0		0
Total equity	(10,901)		(10,170)
Total liabilities and equity	$ (12,963)		$ (11,963)

[1] There were $0 million of accumulated impairment losses as of September 30, 2017.