Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss	Unearned ESOP Shares [Member]	The Dow Chemical Company [Domain]	The Dow Chemical Company [Domain] Common Stock [Member]	The Dow Chemical Company [Domain] Additional Paid-in Capital [Member]	The Dow Chemical Company [Domain] Retained Earnings [Member]	The Dow Chemical Company [Domain] Accumulated Other Comprehensive Loss	The Dow Chemical Company [Domain] Unearned ESOP Shares [Member]	The Dow Chemical Company [Domain] Noncontrolling Interests	Dow Inc. [Member] Retained Earnings [Member]
Total Equity, Beginning at Dec. 31, 2019		$ 8	$ 7,325	$ 17,045	$ (10,246)	$ (91)		$ 0	$ 7,333	$ 17,313	$ (10,246)	$ (91)
Stock Issued									16
Stock-based compensation and allocation of ESOP shares			29			10			29			10
Net income available for The Dow Chemical Company common stockholder	$ 237			239						239
SEC Schedule, 12-04, Cash Dividends Paid to Registrant, Subsidiaries and Equity Method Investees														$ (643)
Other				3						(4)
Other comprehensive income	(283)				(283)		$ (283)				(283)
Total Equity, Ending at Mar. 31, 2020	13,461	8	7,370	16,763	(10,529)	(81)	14,228	0	7,378	16,905	(10,529)	(81)	$ 555
The Dow Chemical Company’s stockholders’ equity	12,906						13,673
The Dow Chemical Company’s stockholders’ equity	12,435						12,999
Total Equity, Beginning at Dec. 31, 2020	13,005	8	7,595	16,361	(10,855)	(49)	13,569	0	7,603	16,300	(10,855)	(49)
Stock Issued									127
Stock-based compensation and allocation of ESOP shares			21			10			21			10
Net income available for The Dow Chemical Company common stockholder	986			991						983
SEC Schedule, 12-04, Cash Dividends Paid to Registrant, Subsidiaries and Equity Method Investees														$ (703)
Other				2						(3)
Other comprehensive income	942				942		942				942
Total Equity, Ending at Mar. 31, 2021	14,563	$ 8	$ 7,743	$ 16,829	$ (9,913)	$ (39)	14,936	$ 0	$ 7,751	$ 16,577	$ (9,913)	$ (39)	$ 560
The Dow Chemical Company’s stockholders’ equity	$ 14,003						$ 14,376