RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Related Party Transaction [Line Items]
Payments of Dividends	$ 40	$ 81
The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Payments of Dividends	40	81
Commodity And Raw Material Purchases \| Cost of Sales [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	483	231
Net Commission Expense \| Sundry Income (Expense), Net [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	6	5
General and Administrative Expense \| Sundry Income (Expense), Net [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	17	8
Activity Based Costs \| Cost of Sales [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 19	$ 23

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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