Consolidated Statements of Equity (USD $) In Millions, unless otherwise specified	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 Income (Loss) [Member]	Unearned ESOP Shares [Member]	Treasury Stock [Member]	Noncontrolling Interests [Member]
Stockholders' Equity Attributable to Parent, Beginning at Dec. 31, 2010			$ 4,000	$ 2,931	$ 2,286	$ 17,736	$ (4,399)	$ (476)	$ (239)
Stockholders' Equity Attributable to Noncontrolling Interest, Beginning at Dec. 31, 2010										803
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued				23	161
Net income attributable to noncontrolling interests	24									24
Net Income available for The Dow Chemical Company common stockholders	2,422					2,422
Dividends declared on common stock (per share: $0.89 in 2012, $0.65 in 2011)						(748)
Other						(10)				(13)
Other comprehensive income	109						109
Purchases									(19)
Issuance to employees and employee plans									258
Distributions to noncontrolling interests										(34)
Capital contributions (noncash capital contributions - 2012: $97; 2011: $0)										20
Consolidation of variable interest entity										31
Conversion of note payable to preferred shares of a subsidiary										158
Stock-based compensation and allocation of ESOP shares					79
Shares Allocated to ESOP participants								38
Stockholders' Equity Attributable to Parent, Ending at Sep. 30, 2011		24,152	4,000	2,954	2,526	19,400	(4,290)	(438)	0
Stockholders' Equity Attributable to Noncontrolling Interest, Ending at Sep. 30, 2011										989
Total Equity, Ending at Sep. 30, 2011	25,141
Stockholders' Equity Attributable to Parent, Beginning at Dec. 31, 2011	22,281		4,000	2,961	2,663	19,087	(5,996)	(434)	0
Stockholders' Equity Attributable to Noncontrolling Interest, Beginning at Dec. 31, 2011	1,010									1,010
Total Equity, Beginning at Dec. 31, 2011	23,291
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued				37	170
Net income attributable to noncontrolling interests	38									38
Net Income available for The Dow Chemical Company common stockholders	1,558					1,558
Dividends declared on common stock (per share: $0.89 in 2012, $0.65 in 2011)						(1,042)
Other						(12)				9
Other comprehensive income	515						515
Purchases									0
Issuance to employees and employee plans									0
Distributions to noncontrolling interests										(60)
Capital contributions (noncash capital contributions - 2012: $97; 2011: $0)										97
Consolidation of variable interest entity										37
Conversion of note payable to preferred shares of a subsidiary										0
Stock-based compensation and allocation of ESOP shares					279
Shares Allocated to ESOP participants								44
Stockholders' Equity Attributable to Parent, Ending at Sep. 30, 2012	23,830	23,830	4,000	2,998	3,112	19,591	(5,481)	(390)	0
Stockholders' Equity Attributable to Noncontrolling Interest, Ending at Sep. 30, 2012	1,131									1,131
Total Equity, Ending at Sep. 30, 2012	$ 24,961