Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123351718&loc=d3e2420-110228

+ Details

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

- Definition

Amount of loss from the write-down 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266

+ Details

Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_RestructuringCostAndReserveLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of restructuring charges, remediation cost, and asset impairment loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

+ Details

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

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=dow_SadaraChemicalCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_ManufacturingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByAssetClassAxis=dow_ManufacturingAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

RESTRUCTURING, GOODWILL IMPAIRMENT AND ASSET RELATED CHARGES - NET (Goodwill Impairment and Asset Related Charges) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges				$ 49
Restructuring, goodwill impairment and asset related charges - net			$ 6	708	$ 3,219
Sadara Chemical Company
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net	$ 1,755
Performance Materials & Coatings [Member]
Restructuring Cost and Reserve [Line Items]
Goodwill, Impairment Loss	1,039
Restructuring, goodwill impairment and asset related charges - net			10	192	1,076
Packaging & Specialty Plastics [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net			8	30	439
Packaging & Specialty Plastics [Member] \| Sadara Chemical Company
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net	370
Corporate Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net			(13)	464	529
Corporate Segment [Member] \| Sadara Chemical Company
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net	217
Industrial Intermediates & Infrastructure [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net			$ 1	22	1,175
Industrial Intermediates & Infrastructure [Member] \| Sadara Chemical Company
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net	$ 1,168
Manufacturing Facility
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges					58
Manufacturing Facility \| Performance Materials & Coatings [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges					9
Manufacturing Facility \| Packaging & Specialty Plastics [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges					44
Manufacturing Facility \| Corporate Segment [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges					5
Fair Value, Measurements, Nonrecurring \| Performance Materials & Coatings [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges				15
Fair Value, Measurements, Nonrecurring \| Packaging & Specialty Plastics [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges				19
Fair Value, Measurements, Nonrecurring \| Corporate Segment [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges				15
Fair Value, Measurements, Nonrecurring \| Manufacturing Assets
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges		$ 75
Fair Value, Measurements, Nonrecurring \| Manufacturing Assets \| Packaging & Specialty Plastics [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges		24
Fair Value, Measurements, Nonrecurring \| Manufacturing Assets \| Corporate Segment [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges		$ 51
Fair Value, Measurements, Nonrecurring \| Manufacturing Facility \| Packaging & Specialty Plastics [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges				$ 19	$ 44