Other (Charges) Gains, Net - Schedule of Restructuring Reserve by Type of Cost (Details) - Employee Severance $ in Millions	6 Months Ended
Jun. 30, 2025 USD ($)
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	$ 63
Additions	51
Cash payments	(76)
Other changes	0
Exchange rate changes	2
Reserve as of the end of the period	40
Engineered Materials
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	57
Additions	31
Cash payments	(60)
Other changes	(4)
Exchange rate changes	2
Reserve as of the end of the period	26
Acetyl Chain [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	0
Additions	4
Cash payments	(2)
Other changes	0
Exchange rate changes	0
Reserve as of the end of the period	2
Corporate Segment and Other Operating Segment [Member]
Restructuring Reserve [Roll Forward]
Reserve as of the beginning of the period	6
Additions	16
Cash payments	(14)
Other changes	4
Exchange rate changes	0
Reserve as of the end of the period	$ 12

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
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-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482047/420-10-45-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-1

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

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