COMMITMENTS AND CONTINGENCIES Nova Ethylene Asset Matter (Details) - Nova Ethylene Asset Matter [Member] $ in Millions, $ in Millions		3 Months Ended
Sep. 18, 2019 CAD ($)	Sep. 18, 2019 USD ($)	Jun. 30, 2025 CAD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Gain Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party	$ 1,430	$ 1,080	$ 1,620	$ 1,200
Estimated Litigation Liability, Noncurrent				$ 201	$ 201

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

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-Topic 210
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