Aggregate Amount of Cross Default Debt Constituting Event of Default.

No definition available.

Name:	ce_AggregateAmountOfCrossDefaultDebtConstitutingEventOfDefault
Namespace Prefix:	ce_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amortization rate of initial principal amount per annum payable quarterly.

+ References

No definition available.

+ Details

Name:	ce_AmortizationRateOfInitialPrincipalAmountPerAnnumPayableQuarterly
Namespace Prefix:	ce_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=ce_EuropeanInterbankOfferedRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ce_TermC2LoanFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ce_AmendedCreditAgreementMember
Namespace Prefix:
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Debt (Senior Notes and Senior Credit Facilities Narrative) (Details) € in Millions, $ in Millions		3 Months Ended
	Mar. 31, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2014 EUR (€)
Term C-3 Loan Facility [Member]
Debt Instrument [Line Items]
Secured Debt	$ 883	$ 883	$ 878
Term C-3 Loan Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Estimated margin	2.25%
Term C-3 Loan Facility [Member] \| European Interbank Offered Rate (EURIBOR) [Member]
Debt Instrument [Line Items]
Estimated margin	2.25%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing base	$ 900	$ 900		$ 900
Amortization rate of initial principal amount per annum payable quarterly		1.00%
Line of credit facility, unused capacity, commitment fee percentage		0.25%
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Estimated margin	1.50%
Term C-2 Loan Facility [Member]
Debt Instrument [Line Items]
Secured Debt	$ 31	$ 31	$ 30		€ 28
Term C-2 Loan Facility [Member] \| European Interbank Offered Rate (EURIBOR) [Member]
Debt Instrument [Line Items]
Estimated margin	2.00%
Amended Credit Agreement [Member]
Debt Instrument [Line Items]
Cross default covenant to other debt	$ 50	$ 50