Equity Method Investment. Percentage of Outstanding Common Stock Purchased

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- Definition

Equity Method Investment, Conversion of Notes Receivable to Equity

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Equity Method Investment, Difference Between Carrying Amount and Underlying Equity, Portion Amortized Over Remaining Useful Life

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- Definition

Equity Method Investment, Liability, Noncurrent

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- Definition

Equity Method Investment, Ownership Interest, Number of Affiliates

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- Definition

Equity Method Investment, Ownership Interest, Shares

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Equity Method Investment, Shares Purchased

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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- Definition

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

The increase (decrease) during the reporting period in the amount owed to the reporting entity in the form of loans and obligations (generally evidenced by promissory notes) made to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due after 1 year (or 1 business cycle).

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- 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.

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NONCONSOLIDATED AFFILIATES (Narrative) (Details) $ in Millions		3 Months Ended		12 Months Ended
	Apr. 04, 2017 shares	Dec. 31, 2018 USD ($) jointventures	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($) jointventures	Dec. 31, 2017 USD ($) jointventures	Dec. 31, 2016 USD ($)	Jul. 31, 2015 USD ($) shares
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Dividends or Distributions				$ 908	$ 865	$ 685
Equity Method Investment, Liability, Noncurrent		$ 495		495	752
Investment in nonconsolidated affiliates		$ 3,823		$ 3,823	$ 3,742
Equity Method Investment, Ownership Interest, Number of Affiliates \| jointventures		51		51	53
Exclusive of additional differences for Dow Corning and MEGlobal
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity		$ 10		$ 10	$ 32
Hemlock Semiconductor LLC
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Liability, Noncurrent		$ (495)		$ (495)	$ 752
Ownership percentage		50.10%	50.10%	50.10%	50.10%	50.10%
EQUATE Petrochemical Company K.S.C.
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity		$ (502)		$ (502)	$ (516)
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity, Portion Amortized Over Remaining Useful Life		184		184	200
Investment in nonconsolidated affiliates		$ 131		$ 131	$ 42
Ownership percentage		42.50%	42.50%	42.50%	42.50%	42.50%
Sadara Chemical Company
Schedule of Equity Method Investments [Line Items]
Ownership percentage		35.00%	35.00%	35.00%	35.00%	35.00%
Equity Method Investment, Conversion of Notes Receivable to Equity		$ 70		$ 312	$ 718
AgroFresh
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity		$ 101		$ 101	$ 92
Investment in nonconsolidated affiliates							$ 210
Equity Method Investment, Additional Information \| shares							17,500,000
Ownership percentage		42.00%		42.00%	36.00%		35.00%
Equity Method Investment, Other than Temporary Impairment			$ 143
Equity Method Investee \| Sadara Chemical Company
Schedule of Equity Method Investments [Line Items]
Noncurrent receivables, Balance Due From Nonconsolidated Affiliates		$ 0		$ 0	$ 275
Increase (Decrease) in Notes Receivable, Related Parties					$ 735
Variable Interest Entity, Not Primary Beneficiary \| AgroFresh
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Shares Purchased \| shares	5,070,358
Dow \| Variable Interest Entity, Not Primary Beneficiary \| AgroFresh
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Shares Purchased \| shares	5,070,358
Equity Method Investment. Percentage of Outstanding Common Stock Purchased	10.00%
Customer Concentration Risk \| Equity Method Investee \| MEGlobal
Schedule of Equity Method Investments [Line Items]
Concentration Risk, Percentage				1.00%	1.00%	1.00%
Customer Concentration Risk \| Equity Method Investee \| HSC Group
Schedule of Equity Method Investments [Line Items]
Concentration Risk, Percentage				1.00%	1.00%
Sadara Chemical Company \| Equity Method Investee \| Sadara Chemical Company
Schedule of Equity Method Investments [Line Items]
Concentration Risk, Percentage				8.00%	3.00%
SCG-Dow Group \| Equity Method Investee \| SCG-Dow Group
Schedule of Equity Method Investments [Line Items]
Concentration Risk, Percentage					2.00%	3.00%
SCG-Dow Group \| Supplier Concentration Risk \| Equity Method Investee \| SCG-Dow Group
Schedule of Equity Method Investments [Line Items]
Concentration Risk, Percentage				2.00%