Charges related to separation, distribution and tax matters agreements

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Supplementary Information [Line Items]

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- Definition

In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of gain (loss) on sale or disposal of other assets.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of increase (decrease) in loss contingency liability.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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Amount of income (expense) related to nonoperating activities, classified as other.

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SUPPLEMENTARY INFORMATION (Sundry Income, Net) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2019	Jun. 30, 2017	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplementary Information [Line Items]
Non-operating pension and other postretirement benefit plan net credit				$ 205	$ 123	$ (676)
Foreign exchange gains (losses)				91	(119)	(72)
Gain (loss) related to litigation settlement				205		137
Charges related to separation, distribution and tax matters agreements				(144)
Loss on early extinguishment of debt				(102)	(54)	0
Gain (loss) on divestiture				(49)	0	7
Gain on sales of other assets and investments				67	18	117
Reclassification of cumulative translation adjustments				10	4	8
Other - net				103	124	65
Sundry income (expense) - net				461	96	(154)
MEGlobal
Supplementary Information [Line Items]
Gain (loss) on divestiture					20
Sundry Income (Expense), Net
Supplementary Information [Line Items]
Charges related to separation, distribution and tax matters agreements			$ (69)	(69)	0	0
Dow Silicones Corporation
Supplementary Information [Line Items]
Gain and post-close adjustments related to Dow Silicones ownership restructure				0	(20)	0
Nova Ethylene Asset Matter [Member]
Supplementary Information [Line Items]
Gain (loss) related to litigation settlement				170	0	0
Commercial Creditors Litigation
Supplementary Information [Line Items]
Loss Contingency Accrual, Period Increase (Decrease)				(50)	0	33
Nova Patent Infringement
Supplementary Information [Line Items]
Gain (loss) related to litigation settlement				0	0	137
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| MEGlobal
Supplementary Information [Line Items]
Gain (loss) on divestiture				0	20	0
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Global Ethylene Acrylic Acid (EAA)
Supplementary Information [Line Items]
Gain (loss) on divestiture				0	0	227
The Dow Chemical Company
Supplementary Information [Line Items]
Non-operating pension and other postretirement benefit plan net credit				205	123	(676)
Foreign exchange gains (losses)				77	(119)	(72)
Loss on early extinguishment of debt				(102)	(54)	0
Gain (loss) on divestiture				2	0	7
Gain on sales of other assets and investments				67	18	117
Reclassification of cumulative translation adjustments				10	4	8
Other - net				103	124	65
Sundry income (expense) - net				573	96	(154)
The Dow Chemical Company \| Sundry Income (Expense), Net
Supplementary Information [Line Items]
Charges related to separation, distribution and tax matters agreements				6	0	0
The Dow Chemical Company \| Dow Silicones Corporation
Supplementary Information [Line Items]
Gain and post-close adjustments related to Dow Silicones ownership restructure				0	(20)	0
The Dow Chemical Company \| Nova Ethylene Asset Matter [Member]
Supplementary Information [Line Items]
Gain (loss) related to litigation settlement				170	0	0
The Dow Chemical Company \| Commercial Creditors Litigation
Supplementary Information [Line Items]
Loss Contingency Accrual, Period Increase (Decrease)				(50)	0	33
The Dow Chemical Company \| Nova Patent Infringement
Supplementary Information [Line Items]
Gain (loss) related to litigation settlement				0	0	137
The Dow Chemical Company \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| MEGlobal
Supplementary Information [Line Items]
Gain (loss) on divestiture				0	20	0
The Dow Chemical Company \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Global Ethylene Acrylic Acid (EAA)
Supplementary Information [Line Items]
Gain (loss) on divestiture				0	0	227
Dow Silicones Corporation \| Commercial Creditors Litigation
Supplementary Information [Line Items]
Loss Contingency Accrual, Period Increase (Decrease)	$ (50)	$ 33
Breast Implant and Other Products Liability Claims
Supplementary Information [Line Items]
Loss Contingency Accrual, Period Increase (Decrease)				85	0	0
Breast Implant and Other Products Liability Claims \| The Dow Chemical Company
Supplementary Information [Line Items]
Loss Contingency Accrual, Period Increase (Decrease)				$ 85	$ 0	$ 0
Breast Implant and Other Products Liability Claims \| Dow Silicones Corporation
Supplementary Information [Line Items]
Loss Contingency Accrual, Period Increase (Decrease)	$ 98