Ceiling amount above which the Company will indemnify Hoechst for.

No definition available.

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- Definition

The amount that the Company will indemnify Hoechst for in full.

+ References

No definition available.

+ Details

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

- Definition

The percentage of the amount above the ceiling that the Company will indemnify Hoechst for.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Percentage of other liabilities the Company has agreed to indemnify Hoechst for as part of the Demerger Agreement.

+ References

No definition available.

+ Details

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

- Definition

Number of divestiture agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

+ Details

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

- 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

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- Definition

Amount of cash outflow reducing loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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Data Type:	na
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- Details

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Commitments and Contingencies (Guarantees - Demerger and Divesture Obligations Narrative) (Details) - 257 months ended Mar. 31, 2021 € in Millions, $ in Millions	USD ($)	EUR (€)	USD ($)
Indemnification Agreements Hoechst [Member]
Loss Contingencies [Line Items]
Number of divestiture agreements		19	19
Indemnification amount \| €		€ 250
Indemnification ceiling amount \| €		€ 750
Indemnification percentage exceeding ceiling amount		33.33%	33.33%
Loss contingency accrual, carrying value, payments \| $	$ 97
Indemnification percentage, other		33.33%	33.33%
Divestiture Agreements [Member]
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure \| $			$ 116