Aggregate Amount of Cross Default Debt Constituting Event of Default.

No definition available.

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Namespace Prefix:	ce_
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Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Year of Maturity Date.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Redemption Price as Percentage of Principal Amount.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

+ Details

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Balance Type:	credit
Period Type:	duration

- 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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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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- Details

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- Definition

For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16

-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 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

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Namespace Prefix:	us-gaap_
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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

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- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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Debt (Narrative) (Details)	12 Months Ended				12 Months Ended					12 Months Ended				1 Months Ended		12 Months Ended		1 Months Ended	12 Months Ended					12 Months Ended
Debt (Narrative) (Details)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	May 06, 2011 USD ($)	Dec. 31, 2011 Term B Loan Facility [Member] USD ($)	Dec. 31, 2010 Term B Loan Facility [Member] USD ($)	May 05, 2011 Term B Loan Facility [Member] USD ($)	Sep. 30, 2010 Term B Loan Facility [Member] US Dollar Denominated [Member] USD ($)	Sep. 30, 2010 Term B Loan Facility [Member] Euro Denominated [Member] EUR (€)	Dec. 31, 2011 Term C Loan Facility [Member] USD ($)	Dec. 31, 2010 Term C Loan Facility [Member] USD ($)	Sep. 30, 2010 Term C Loan Facility [Member] US Dollar Denominated [Member] USD ($)	Sep. 30, 2010 Term C Loan Facility [Member] Euro Denominated [Member] EUR (€)	Apr. 30, 2011 Senior Unsecured Notes Due 2018 [Member] USD ($)	Sep. 30, 2010 Senior Unsecured Notes Due 2018 [Member] USD ($)	Dec. 31, 2011 Senior Unsecured Notes Due 2018 [Member]	Dec. 31, 2010 Senior Unsecured Notes Due 2018 [Member]	May 31, 2011 Senior Unsecured Notes Due 2021 [Member] USD ($)	Dec. 31, 2011 Senior Unsecured Notes Due 2021 [Member]	Dec. 31, 2010 Senior Unsecured Notes Due 2021 [Member]	Dec. 31, 2010 Revolving Credit Facility [Member]	Dec. 31, 2011 Revolving Credit Facility [Member] USD ($)	Sep. 30, 2010 Revolving Credit Facility [Member] USD ($)	Dec. 31, 2010 Credit-linked Revolving Facility [Member]	Sep. 30, 2010 Credit-linked Revolving Facility [Member] USD ($)	Dec. 31, 2011 Amended Credit Agreement [Member] USD ($)
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	2014				2016	2016				2018	2018	2018	2021	2021	2021
Notes redemption price															100.00%			100.00%
Senior notes exchange offer, amount														600,000,000
Accelerated amortization of deferred financing costs	3,000,000	16,000,000	0
Deferred financing costs				8,000,000
Senior credit facility					0	508,000,000	516,000,000	417,000,000	69,000,000	1,386,000,000	1,409,000,000	1,140,000,000	204,000,000									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