Income taxes liability reclassified to (from) current from noncurrent

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- Definition

Ownership Interest Percentage, Related Company

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- Definition

Costs of sales and operating expenses for the period incurred from transactions with related parties.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

The increase (decrease) during the reporting period in income taxes receivable, which represents the amount due from tax authorities for refunds of overpayments or recoveries of income taxes paid.

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- Definition

Amount of dividend income on nonoperating securities.

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- Definition

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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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.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Related Party Transaction [Line Items]
Short-term Lease Cost	$ 13		$ 18	$ 47	$ 40
Increase (Decrease) in Income Taxes Receivable					220
Income taxes liability reclassified to (from) current from noncurrent	$ 49	$ 219
Payments of Dividends				28	228
Investment Income, Dividend				$ 4
Effective Income Tax Rate Reconciliation, Percent	1.80%			(1.10%)
The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Short-term Lease Cost	$ 4		4	$ 11	11
Payments of Dividends	0		42	$ 28	228
Dow International Holdings Company [Member]
Related Party Transaction [Line Items]
Investment Income, Dividend	$ 735
Ownership Interest Percentage, Related Company	4.70%			4.70%
Activity Based Costs \| Cost of Sales [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Costs and Expenses, Related Party	$ 169		154	$ 531	445
Commodity And Raw Material Purchases \| Cost of Sales [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Costs and Expenses, Related Party	287		229	803	728
Net Commission Expense \| Sundry Income (Expense), Net [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Costs and Expenses, Related Party	5		5	14	15
General and Administrative Expense \| Sundry Income (Expense), Net [Member] \| The Dow Chemical Company [Member]
Related Party Transaction [Line Items]
Costs and Expenses, Related Party	$ 17		$ 14	$ 53	$ 40