Description of the Plan - Narrative (Details) - EBP 001	1 Months Ended	12 Months Ended
Jan. 31, 2025 USD ($)	Dec. 31, 2025 USD ($) loan year
EBP, Description of Plan [Line Items]
Net transfers into (from) plan	$ 117,000,000.0	$ 116,813,000
Salary deferral, automatic deferral rate		6.00%
Retirement age \| year		65
Requisite service period, consecutive months		1 year
Employer contribution, participant compensation matched, percentage		6.00%
Employer contribution, annual retirement contribution, percentage		0.05
Forfeited nonvested account		$ 299,934
Note receivable minimum borrowing amount		1,000
Note receivable maximum borrowing amount		$ 50,000
Note receivable from participant, general loan, maximum borrowing term		5 years
Participant loan, basis spread on variable rate		0.01
Plan participants, increments percentage		1.00%
Note receivable from participant, maximum number of notes outstanding \| loan		1
EBP, Qualified Non-Elective Contributions
EBP, Description of Plan [Line Items]
Participant contribution, annual compensation to total compensation, percentage		0.75
EBP, Active Participants
EBP, Description of Plan [Line Items]
Note receivable minimum borrowing amount		$ 2,000
Note receivable maximum borrowing as percentage of total account		50.00%
Note receivable maximum borrowing amount		$ 50,000
Minimum
EBP, Description of Plan [Line Items]
Salary deferral automatic yearly increase to deferral rate		1.00%
Rate of Interest		4.30%
Maximum
EBP, Description of Plan [Line Items]
Salary deferral automatic yearly increase to deferral rate		15.00%
Employer contribution vesting service period		3 years
Rate of Interest		9.50%

EBP, Employer Contribution, Annual Retirement Contribution, Percentage

No definition available.

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- Definition

Minimum Vesting service period for company contribution and/ or investment earning to the participant in Company Matching Contributions, Fixed Rate Contributions, Discretionary Profit-Sharing Contributions, Qualified Non-Elective Contributions, and Disability Contributions.

+ References

No definition available.

+ Details

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- Definition

EBP, Investment, Plan Participants, Increments Percentage

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

EBP, Note Receivable from Participant, Maximum Number of Notes Outstanding

+ References

No definition available.

+ Details

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Namespace Prefix:	ce_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Annual Compensation To Total Compensation, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	ce_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Annual Increase Deferral Rate

+ References

No definition available.

+ Details

Name:	ce_EBPParticipantContributionAutomaticAnnualIncreaseDeferralRate
Namespace Prefix:	ce_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

Name:	ce_EBPParticipantLoanBasisSpreadOnVariableRate
Namespace Prefix:	ce_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Requisite Service Period, Consecutive Months

+ References

No definition available.

+ Details

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Namespace Prefix:	ce_
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- Definition

EBP, Retirement Age

+ References

No definition available.

+ Details

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Namespace Prefix:	ce_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of net asset available for benefit transferred to (from) employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from (to) external plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule III))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 45
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477063/962-205-45-8

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
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Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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- Details

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- Details

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- Details

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- Details

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