Asset Retirement Obligations, Estimated Remaining Useful Life

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

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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.

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No definition available.

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Amount of investment in marketable security.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Amount of current assets classified as other.

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

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

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

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- Definition

The increase (decrease) in stockholders' equity during the period.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative - USD ($) $ / shares in Units, $ in Millions				3 Months Ended								12 Months Ended
	Jan. 01, 2019	Apr. 01, 2018	Jan. 01, 2018	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Percentage of LIFO Inventory				30.00%				32.00%				30.00%	32.00%
Percentage of FIFO Inventory				58.00%				58.00%				58.00%	58.00%
Percentage of Weighted Average Cost Inventory				12.00%				10.00%				12.00%	10.00%
Operating Lease, Right-of-Use Asset				$ 1,856				$ 2,072				$ 1,856	$ 2,072
Operating Lease, Liability				$ 1,937								$ 1,937
Dividends declared (in dollars per share)				$ 0.70	$ 0.70	$ 0.70	$ 0.70	$ 0.70	$ 0.70	$ 0.70		$ 2.80	$ 2.10	$ 0
Other current assets				$ 889				$ 679				$ 889	$ 679
Minimum
Useful life												3 years
Maximum
Useful life												20 years
Asset retirement obligations, estimated remaining useful life												10 years
The Dow Chemical Company
Marketable securities 2								0					0
Other current assets								592					592
The Dow Chemical Company \| Previously Reported [Member]
Marketable securities 2								21					21
Other current assets								571					$ 571
Dow Inc. [Member]
Dividends declared (in dollars per share)												$ 2.80	$ 2.10
Marketable securities 2								0					$ 0
Other current assets								679					679
Dow Inc. [Member] \| Previously Reported [Member]
Marketable securities 2								21					21
Other current assets								$ 658					$ 658
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset	$ 2,300
Stockholders' Equity, Period Increase (Decrease)											$ 32
Retained Earnings [Member]
Stockholders' Equity, Period Increase (Decrease)	$ 183	$ 1,057	$ 68
AOCI Attributable to Parent [Member]
Stockholders' Equity, Period Increase (Decrease)			$ 20