Consolidated Statements of Comprehensive Loss - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 4,633	$ 595	$ 4,404
Other comprehensive income (loss), net of tax
Unrealized losses on investments	(67)	(46)	(4)
Cumulative translation adjustments	(225)	900	(644)
Pension and other postretirement benefit plans	(40)	391	(620)
Derivative instruments	75	(14)	113
Total other comprehensive income (loss)	(257)	1,231	(1,155)
Comprehensive income	4,376	1,826	3,249
Comprehensive income attributable to noncontrolling interests, net of tax	97	172	83
Comprehensive income attributable to The Dow Chemical Company	$ 4,279	$ 1,654	$ 3,166

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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