SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Percentage of LIFO Inventory	34.00%	32.00%
Percentage of FIFO Inventory	57.00%	59.00%
Percentage of Weighted Average Cost Inventory	9.00%	9.00%
Dividends declared (in dollars per share)		$ 1.38	$ 1.84
Minimum
Useful life	3 years
Maximum
Useful life	20 years
Asset retirement obligations, estimated remaining useful life	10 years
The Dow Chemical Company [Domain]
Dividends declared (in dollars per share)		$ 1.38	$ 1.84

Asset Retirement Obligations, Estimated Remaining Useful Life

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The percentage of FIFO (first in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

+ References

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- Definition

The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

+ References

No definition available.

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- Definition

The percentage of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods.

+ References

No definition available.

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