Consolidated Statements of Equity - USD ($) $ in Millions	Total	The Dow Chemical Company's Stockholder's Equity [Member]	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 [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity Attributable to Noncontrolling Interest										$ 1,026
Stockholders' Equity Attributable to Parent, Beginning at Dec. 31, 2013			$ 4,000	$ 3,054	$ 3,928	$ 21,407	$ (4,827)	$ (357)	$ (307)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued				53
Common Stock Issued/Sold Additional Paid in Capital					840
Stock-based compensation and allocation of ESOP shares					(20)
Net income available for The Dow Chemical Company common stockholders	$ 2,698					2,698
Dividends declared on common stock (per share - 2015: $1.26; 2014: $1.11)						(1,299)
Other					(7)	(14)				(1)
Other comprehensive loss	(544)						(544)
Shares Allocated to ESOP participants								20
Purchases									(3,100)
Issuances - compensation plans									206
Total Equity, Ending at Sep. 30, 2014	26,711
Stockholders' Equity Attributable to Parent, Ending at Sep. 30, 2014		$ 25,731	4,000	3,107	4,741	22,792	(5,371)	(337)	(3,201)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity Attributable to Noncontrolling Interest										982
Net income available for The Dow Chemical Company common stockholders	852
Other										(2)
Other comprehensive loss	(642)
Total Equity, Ending at Sep. 30, 2014	26,711
Stockholders' Equity Attributable to Parent, Ending at Sep. 30, 2014		25,731	4,000	3,107	4,741	22,792	(5,371)	(337)	(3,201)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity Attributable to Noncontrolling Interest										980
Stockholders' Equity Attributable to Noncontrolling Interest	931									931
Total Equity, Beginning at Dec. 31, 2014	23,354
Stockholders' Equity Attributable to Parent, Beginning at Dec. 31, 2014	22,423		4,000	3,107	4,846	23,045	(8,017)	(325)	(4,233)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued				0
Common Stock Issued/Sold Additional Paid in Capital					313
Stock-based compensation and allocation of ESOP shares					(277)
Net income available for The Dow Chemical Company common stockholders	3,818					3,818
Dividends declared on common stock (per share - 2015: $1.26; 2014: $1.11)						(1,436)
Other					18	(16)				3
Other comprehensive loss	(568)						(568)
Shares Allocated to ESOP participants								47
Purchases									(500)
Issuances - compensation plans									511
Total Equity, Ending at Sep. 30, 2015	25,166
Stockholders' Equity Attributable to Parent, Ending at Sep. 30, 2015	24,333	24,333	4,000	3,107	4,900	25,411	(8,585)	(278)	(4,222)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity Attributable to Noncontrolling Interest										839
Net income available for The Dow Chemical Company common stockholders	1,290
Other										3
Other comprehensive loss	(175)
Total Equity, Ending at Sep. 30, 2015	25,166
Stockholders' Equity Attributable to Parent, Ending at Sep. 30, 2015	24,333	$ 24,333	$ 4,000	$ 3,107	$ 4,900	$ 25,411	$ (8,585)	$ (278)	$ (4,222)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity Attributable to Noncontrolling Interest	$ 833									$ 833