OPERATING SEGMENTS AND GEOGRAPHIC AREAS (Schedule of Operating Segments) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Sales to external customers	$ 13,230	$ 10,703
Income before income taxes excluding interest, depreciation and amortization and certain items	2,704	2,253
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	196	39
Agricultural Sciences [Member]
Segment Reporting Information [Line Items]
Sales to external customers	1,568	1,646
Income before income taxes excluding interest, depreciation and amortization and certain items	351	403
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	(1)	7
Consumer Solutions [Member]
Segment Reporting Information [Line Items]
Sales to external customers	1,599	1,054
Income before income taxes excluding interest, depreciation and amortization and certain items	500	310
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	40	20
Infrastructure Solutions [Member]
Segment Reporting Information [Line Items]
Sales to external customers	2,525	1,594
Income before income taxes excluding interest, depreciation and amortization and certain items	511	293
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	55	51
Performance Materials & Chemicals [Member]
Segment Reporting Information [Line Items]
Sales to external customers	2,442	2,181
Income before income taxes excluding interest, depreciation and amortization and certain items	435	335
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	73	(31)
Performance Plastics [Member]
Segment Reporting Information [Line Items]
Sales to external customers	5,025	4,165
Income before income taxes excluding interest, depreciation and amortization and certain items	984	991
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	33	(1)
Corporate [Member]
Segment Reporting Information [Line Items]
Sales to external customers	71	63
Income before income taxes excluding interest, depreciation and amortization and certain items	(77)	(79)
Equity in earnings (losses) of nonconsolidated affiliates by segment (included in Operating EBITDA)	$ (4)	$ (7)

Income before income taxes excluding interest, depreciation and amortization and certain items

No definition available.

Name:	dow_Incomebeforeincometaxesexcludinginterestdepreciationandamortizationandcertainitems
Namespace Prefix:	dow_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

Name:	us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

+ Details

Name:	us-gaap_SalesRevenueNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=dow_AgriculturalSciencesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=dow_ConsumerSolutionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=dow_InfrastructureSolutionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=dow_PerformanceMaterialsChemicalsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=dow_PerformancePlasticsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_MaterialReconcilingItemsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: