Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Add'l Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Unearned ESOP	Treasury Stock
Beginning balance at Dec. 31, 2018		$ 0	$ 7,042	$ 35,460	$ (9,885)	$ (134)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		8
Common stock issued/sold			57
Issuance of parent company stock			28
Stock-based compensation and allocation of ESOP shares			235			45
Other			(37)	(14)
Net income (loss) available for The Dow Chemical Company common stockholder	$ (1,359)			(1,359)
Dividends to stockholders				(1,550)
Dividends to parent				(535)
Settlements and transfers related to separation from DowDuPont Inc.	1,935			(14,806)	793
Stockholders' Equity, Period Increase (Decrease) | Accounting Standards Update 2014-09				(151)
Other comprehensive income (loss)	(1,154)				(1,154)
ESOP shares acquired						(2)
Treasury stock purchases							(500)
Ending balance at Dec. 31, 2019	$ 14,094	8	7,325	17,045	(10,246)	(91)	(500)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share of common stock	$ 2.10
Dow Inc.’s stockholders’ equity	$ 13,541
Noncontrolling interests	553
Common stock issued		0
Common stock issued/sold			108
Issuance of parent company stock			0
Stock-based compensation and allocation of ESOP shares			162			42
Other			0	(15)
Net income (loss) available for The Dow Chemical Company common stockholder	1,225			1,225
Dividends to stockholders				(2,071)
Dividends to parent				0
Settlements and transfers related to separation from DowDuPont Inc.	0			177	0
Stockholders' Equity, Period Increase (Decrease) | Accounting Standards Update 2014-09				0
Other comprehensive income (loss)	(609)				(609)
ESOP shares acquired						0
Treasury stock purchases							(125)
Ending balance at Dec. 31, 2020	$ 13,005	8	7,595	16,361	(10,855)	(49)	(625)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share of common stock	$ 2.80
Dow Inc.’s stockholders’ equity	$ 12,435
Noncontrolling interests	570
Common stock issued		0
Common stock issued/sold			320
Issuance of parent company stock			0
Stock-based compensation and allocation of ESOP shares			236			34
Other			0	(22)
Net income (loss) available for The Dow Chemical Company common stockholder	6,311			6,311
Dividends to stockholders				(2,073)
Dividends to parent				0
Settlements and transfers related to separation from DowDuPont Inc.	0			46	0
Stockholders' Equity, Period Increase (Decrease) | Accounting Standards Update 2014-09				0
Other comprehensive income (loss)	1,878				1,878
ESOP shares acquired						0
Treasury stock purchases							(1,000)
Ending balance at Dec. 31, 2021	$ 18,739	$ 8	$ 8,151	$ 20,623	$ (8,977)	$ (15)	$ (1,625)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share of common stock	$ 2.80
Dow Inc.’s stockholders’ equity	$ 18,165
Noncontrolling interests	$ 574