Common Stock, Related Company

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- Definition

Ownership Interest Percentage, Related Company

+ References

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- Definition

Treasury Stock, Shares, Constructively Retired

+ References

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=29638308&loc=d3e40346-111594

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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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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No definition available.

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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

+ Details

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INVESTMENTS IN RELATED COMPANIES (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Sep. 18, 2015	Dec. 31, 2014	Sep. 30, 2014
Schedule of Cost-method Investments [Line Items]
Investments in related companies	$ 639			$ 813
Treasury Stock, Shares, Constructively Retired	64.49	64.58
Dow International Holdings Company [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments	$ 633			$ 807
Common Stock, Related Company			462.7096
Ownership Interest Percentage, Related Company	15.00%	15.00%	19.10%	19.00%
Investments in related companies		$ 174
Dow Quimica Argentina S.A. [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments	$ 0			$ 0
Ownership Interest Percentage, Related Company	23.00%			23.00%
Dow Quimica Mexicana S.A. de C.V. [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments	$ 5			$ 5
Ownership Interest Percentage, Related Company	15.00%			15.00%
Other Investments [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments	$ 1			$ 1
Ownership Interest Percentage, Related Company	0.00%			0.00%
The Dow Chemical Company [Member]
Schedule of Cost-method Investments [Line Items]
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions		100.00%
GWN Holding, Inc. [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments					$ 10
Ownership Interest Percentage, Related Company					6.30%
The Dow Chemical Company [Member] \| Dow International Holdings Company [Member]
Schedule of Cost-method Investments [Line Items]
Ownership Interest Percentage, Related Company			80.90%
The Dow Chemical Company [Member] \| GWN Holding, Inc. [Member]
Schedule of Cost-method Investments [Line Items]
Ownership Interest Percentage, Related Company					93.70%