Dow Consolidated Statements of Income Statement - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net sales	$ 10,764	$ 12,634	$ 32,747	$ 37,660
Cost of sales	9,377	10,456	27,939	30,976
Research and development expenses	194	193	592	622
Selling, general and administrative expenses	388	409	1,258	1,376
Amortization of intangibles	100	117	320	353
Restructuring and asset related charges - net	147	48	368	175
Integration and separation costs	164	313	964	799
Equity in earnings (losses) of nonconsolidated affiliates	(44)	135	(73)	529
Sundry income (expense) - net	301	(3)	369	37
Interest income	19	22	58	60
Interest expense and amortization of debt discount	233	258	711	781
Income from continuing operations before income taxes	437	994	949	3,204
Provision for income taxes on continuing operations	90	280	356	755
Income from continuing operations, net of tax	347	714	593	2,449
Income from discontinued operations, net of tax	0	335	445	1,403
Net income	347	1,049	1,038	3,852
Net income attributable to noncontrolling interests	14	36	74	102
Net income available for Dow Inc. common stockholders	$ 333	$ 1,013	$ 964	$ 3,750
Earnings per common share from continuing operations - basic	$ 0.45	$ 0.91	$ 0.71	$ 3.17
Earnings per common share from discontinued operations - basic	0	0.45	0.58	1.85
Earnings per common share - basic	0.45	1.36	1.29	5.02
Earnings per common share from continuing operations - diluted	0.45	0.91	0.71	3.17
Earnings per common share from discontinued operations - diluted	0	0.45	0.58	1.85
Earnings per common share - diluted	$ 0.45	$ 1.36	$ 1.29	$ 5.02
Weighted-average common shares outstanding - basic	739.8	747.2	743.3	747.2
Weighted-average common shares outstanding - diluted	743.0	747.2	746.1	747.2
Depreciation	$ 540	$ 549	$ 1,621	$ 1,643
Capital expenditures	$ 472	$ 577	$ 1,384	$ 1,445