Consolidated Statements of Equity - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss	Unearned ESOP Shares [Member]	Treasury Stock [Member]	Noncontrolling Interests
Total Equity, Beginning at Dec. 31, 2015	$ 26,183	$ 4,000	$ 3,107	$ 4,936	$ 28,425	$ (8,667)	$ (272)	$ (6,155)	$ 809
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income available for The Dow Chemical Company common stockholder	4,011				4,011
Other comprehensive income (loss)	986					986
Dividends	(1,531)				(1,531)
Common stock issued / sold	926			320				606
Stock-based compensation and allocation of ESOP shares	(294)			(340)			46
Impact of noncontrolling interests	505								505
Treasury stock purchases	(416)							(416)
Other	21				(21)
Total Equity, Ending at Sep. 30, 2016	30,349	4,000	3,107	4,916	30,884	(7,681)	(226)	(5,965)	1,314
Total Equity, Beginning at Dec. 31, 2016	27,229	0	3,107	4,262	30,338	(9,822)	(239)	(1,659)	1,242
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income available for The Dow Chemical Company common stockholder	2,992				2,992
Other comprehensive income (loss)	1,027					1,027
Dividends	(1,673)				(1,673)
Common stock issued / sold	1,147			423				724
Issuance of parent company stock	21			21
Stock-based compensation and allocation of ESOP shares	(396)			(443)			47
Impact of noncontrolling interests	(53)								(53)
Merger impact	0
Stock Repurchased and Retired During Period, Value			(3,107)	2,172				935
Other	23			2	(21)
Total Equity, Ending at Sep. 30, 2017	$ 30,271	$ 0	$ 0	$ 6,433	$ 31,636	$ (8,795)	$ (192)	$ 0	$ 1,189