SUPPLEMENTARY INFORMATION (Sundry Income, Net) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Supplementary Information [Line Items]
Total sundry income (expense) - net	$ (11)	$ 16	$ (22)
Net gain on sales of property	23	50	(3)
Interest income	20	14	8
Gain (Loss) on Sale of Equity Investments	4	0	0
Nonmonetary Transaction, Gain (Loss) Recognized on Transfer	0	0	23
Foreign exchange loss	0	1	(2)
Other Cost and Expense, Operating	(3)	0	(6)
Administrative and overhead fees [Member] \| The Dow Chemical Company [Member]
Supplementary Information [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	(33)	(27)	(30)
Net Commission Expense [Member]
Supplementary Information [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	(22)	(22)	(22)
Patents [Member]
Supplementary Information [Line Items]
Net gain on sale of assets	$ 0	$ 0	$ 10

Supplementary Information [Line Items]

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Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

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Disclosure of the difference in values (gain (loss)) between the nonmonetary assets or liabilities exchanged with another entity inclusive of boot (small monetary consideration).

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