Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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

- Definition

Amount of other (increase) decrease of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

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

- Details

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

- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=dow_ANGUSChemicalCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=dow_SodiumBorohydridebusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- 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:

GOODWILL AND OTHER INTANGIBLE ASSETS (Goodwill By Operating Segment) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Feb. 02, 2015	Jan. 30, 2015
Goodwill [Line Items]
Goodwill, Acquired During Period	$ 31us-gaap_GoodwillAcquiredDuringPeriod
Goodwill [Roll Forward]
Net goodwill, beginning balance	12,632us-gaap_Goodwill
Foreign currency impact	(143)
Net goodwill, ending balance	12,183us-gaap_Goodwill
Agricultural Sciences [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	0
Goodwill, Acquired During Period	31
Goodwill [Roll Forward]
Net goodwill, beginning balance	1,558
Foreign currency impact	0
Net goodwill, ending balance	1,589
Consumer Solutions [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	0
Goodwill, Acquired During Period	0
Goodwill [Roll Forward]
Net goodwill, beginning balance	4,389
Foreign currency impact	(17)
Net goodwill, ending balance	4,372
Infrastructure Solutions [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	0
Goodwill, Acquired During Period	0
Goodwill [Roll Forward]
Net goodwill, beginning balance	4,451
Foreign currency impact	(79)
Net goodwill, ending balance	4,372
Performance Materials & Chemicals [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	0
Goodwill [Roll Forward]
Net goodwill, beginning balance	809
Foreign currency impact	(11)
Net goodwill, ending balance	461
Performance Plastics [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	0
Goodwill, Acquired During Period	0
Goodwill [Roll Forward]
Net goodwill, beginning balance	1,425
Foreign currency impact	(36)
Net goodwill, ending balance	1,389
ANGUS Chemical Company [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	(292)
ANGUS Chemical Company [Member] \| Performance Materials & Chemicals [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	(292)
Goodwill [Roll Forward]
Net goodwill, beginning balance		292
Net goodwill, ending balance		292
Sodium Borohydride business [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	(45)
Sodium Borohydride business [Member] \| Performance Materials & Chemicals [Member]
Goodwill [Line Items]
Goodwill, Divested During Period	(45)
Goodwill [Roll Forward]
Net goodwill, beginning balance			45
Net goodwill, ending balance			$ 45