Indemnification Asset

No definition available.

Name:	dow_IndemnificationAsset
Namespace Prefix:	dow_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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.

+ References

No definition available.

+ Details

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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=120395209&loc=SL114868664-224227

+ Details

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Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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COMMITMENTS AND CONTINGENT LIABILITIES (Environmental Matters) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies	$ 1,216		$ 1,216	$ 1,155
Restructuring and asset related charges - net	617	$ 147	719
Accrual for Environmental Loss Contingencies, Revision in Estimates		399
2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	575
Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	81
Environmental Remediation [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	56
Cost of Sales
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Revision in Estimates		399
Performance Materials & Coatings [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Revision in Estimates		50
Performance Materials & Coatings [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	174
Performance Materials & Coatings [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	57
Performance Materials & Coatings [Member] \| Environmental Remediation [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	52
Corporate Segment [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Revision in Estimates		336
Corporate Segment [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	368
Corporate Segment [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	24
Corporate Segment [Member] \| Environmental Remediation [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	4
Packaging & Specialty Plastics [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Revision in Estimates		5
Packaging & Specialty Plastics [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	11
Packaging & Specialty Plastics [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	0
Industrial Intermediates & Infrastructure [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Revision in Estimates		8
Industrial Intermediates & Infrastructure [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	22
Industrial Intermediates & Infrastructure [Member] \| Costs Associated with Exit and Disposal Activities [Member] \| 2020 Restructuring Program [Member]
Loss Contingencies [Line Items]
Restructuring and asset related charges - net	0
Dow Silicones Corporation [Member]
Loss Contingencies [Line Items]
Indemnification Asset	115		115	100
Environmental Issue [Member] \| Dow Silicones Corporation [Member]
Loss Contingencies [Line Items]
Indemnification Asset	50	$ 48	50
Accrual For Environmental Loss Contingencies Superfund Sites [Member]
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies	$ 207		$ 207	$ 207