Percentage investment held by members of the Acetate Tow Joint Venture.

No definition available.

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- Definition

The amount of net earnings as a percent of the acquirer's net earnings in a business combination

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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Balance Type:	debit
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- Definition

This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50% or less owned persons accounted for using the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(b))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.9-06)
-URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537971-122884

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

The net cash inflow or outflow in aggregate debt due to repayments and proceeds from additional borrowings.

+ References

No definition available.

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Acquisitions, Dispositions and Plant Closures Acquisition Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 18, 2017	May 03, 2017	Dec. 01, 2016
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount		$ 3,661
Cash Dividends Paid to Parent Company		0	$ 0	$ 0
Nilit [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		3
Business Combination, Net Earnings as a Percent of Acquirer's Net earnings						1.00%
Advanced Engineered Materials [Member] \| Nilit [Member]
Business Acquisition [Line Items]
Goodwill, Purchase Accounting Adjustments		(2)
Advanced Engineered Materials [Member] \| SO.F.TER. S.p.A. [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired							100.00%
Goodwill, Purchase Accounting Adjustments		$ (6)
Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					$ 2,400
Proceeds from (Repayments of) Debt	$ 2,200
Scenario, Plan [Member] \| Celanese [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Acetate Tow JV Ownership Percentages		70.00%
Cash Dividends Paid to Parent Company	$ 1,600
Scenario, Plan [Member] \| Blackstone [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Acetate Tow JV Ownership Percentages		30.00%
Senior Secured JV Revolving Credit Facility [Member] \| Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					135
Senior Unsecured JV Revolving Credit Facility [Member] \| Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					65
Revolving Credit Facility [Member] \| Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					200
Senior Unsecured JV bridge facility [Member] \| Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					800
Senior Secured JV term loan [Member] \| Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					1,000
Senior Unsecured JV term loan facility [Member] \| Scenario, Plan [Member] \| AcetateTowJointVenture [Member]
Business Acquisition [Line Items]
Debt, Long-term and Short-term, Combined Amount					$ 400