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

Debt Instrument, Year of Maturity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ce_
Data Type:	us-types:dateStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Redemption Price as Percentage of Principal Amount.

+ References

No definition available.

+ Details

Name:	ce_RedemptionPriceAsPercentageOfPrincipalAmount
Namespace Prefix:	ce_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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

- Definition

Interest rate stated in the contractual debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Details

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

- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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

- Definition

Reflects when the credit facility terminates, which may be presented in a variety of ways (year, month and year, day, month and year, quarter).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Reference 3: 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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Data Type:	us-types:dateStringItemType
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

+ Details

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

Debt (Narrative) (Details) (USD $)	1 Months Ended		6 Months Ended	12 Months Ended	1 Months Ended	6 Months Ended	12 Months Ended	1 Months Ended	6 Months Ended	12 Months Ended	9 Months Ended		9 Months Ended
Debt (Narrative) (Details) (USD $)	May 31, 2011 Term B Loan Facility [Member]	May 05, 2011 Term B Loan Facility [Member]	Jun. 30, 2012 Term C Loan Facility [Member]	Dec. 31, 2011 Term C Loan Facility [Member]	Sep. 30, 2010 Senior Unsecured Notes Due 2018 [Member]	Jun. 30, 2012 Senior Unsecured Notes Due 2018 [Member]	Dec. 31, 2011 Senior Unsecured Notes Due 2018 [Member]	May 31, 2011 Senior Unsecured Notes Due 2021 [Member]	Jun. 30, 2012 Senior Unsecured Notes Due 2021 [Member]	Dec. 31, 2011 Senior Unsecured Notes Due 2021 [Member]	Sep. 30, 2010 Revolving Credit Facility [Member]	Jun. 30, 2012 Revolving Credit Facility [Member]	Sep. 30, 2010 Credit-Linked Revolving Facility [Member]	Jun. 30, 2012 Amended Credit Agreement [Member]
Debt Instrument [Line Items]
Senior notes					$ 600,000,000			$ 400,000,000
Interest rate, stated percentage					6.625%	6.625%	6.625%	5.875%	5.875%	5.875%
Year of maturity	2014		2016	2016	2018	2018	2018	2021	2021	2021
Notes redemption price					100.00%			100.00%
Senior credit facilities		516,000,000	1,372,000,000	1,386,000,000								0
Revolving credit facility borrowing capacity											600,000,000	600,000,000	228,000,000
Revolving credit facility, expiration date											2015		2014
Cross default covenant to other debt														$ 40,000,000