Dow Consolidated Statements of Income Statement - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Net sales	$ 9,712	$ 10,764	$ 27,836	$ 32,747
Cost of sales	8,371	9,377	24,211	27,939
Research and development expenses	193	194	554	592
Selling, general and administrative expenses	372	388	1,063	1,258
Amortization of intangibles	100	100	300	320
Restructuring and asset related charges - net	617	147	719	368
Integration and separation costs	63	164	174	964
Equity in earnings (losses) of nonconsolidated affiliates	60	(44)	(124)	(73)
Sundry income (expense) - net	182	301	154	369
Interest income	6	19	27	58
Interest expense and amortization of debt discount	202	233	617	711
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest, Total	42	437	255	949
Provision for income taxes on continuing operations	43	90	215	356
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	(1)	347	40	593
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	0	0	445
Net income (loss)	(1)	347	40	1,038
Net income attributable to noncontrolling interests	24	14	51	74
Net income (loss) available for Dow Inc. common stockholders	$ (25)	$ 333	$ (11)	$ 964
Earnings (loss) per common share from continuing operations - basic	$ (0.04)	$ 0.45	$ (0.02)	$ 0.71
Earnings per common share from discontinued operations - basic	0	0	0	0.58
Earnings (loss) per common share - basic	(0.04)	0.45	(0.02)	1.29
Earnings (loss) per common share from continuing operations - diluted	(0.04)	0.45	(0.02)	0.71
Earnings per common share from discontinued operations - diluted	0	0	0	0.58
Earnings (loss) per common share - diluted	$ (0.04)	$ 0.45	$ (0.02)	$ 1.29
Weighted-average common shares outstanding - basic	740.5	739.8	740.0	743.3
Weighted-average common shares outstanding - diluted	740.5	743.0	740.0	746.1
Depreciation	$ 526	$ 540	$ 1,558	$ 1,621
Capital expenditures	$ 287	$ 472	$ 955	$ 1,384