Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 586	$ 1,377
Other comprehensive income (loss), net of tax
Unrealized gains (losses) on investments	67	(25)
Cumulative translation adjustments	(31)	376
Pension and other postretirement benefit plans	141	126
Derivative instruments	(75)	6
Total other comprehensive income	102	483
Comprehensive income	688	1,860
Comprehensive income attributable to noncontrolling interests, net of tax	51	28
Comprehensive income attributable to The Dow Chemical Company	$ 637	$ 1,832

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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