Dow Consolidated Statements of Income Statement - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 11,014	$ 12,789	$ 21,983	$ 25,026
Cost of sales	9,420	10,540	18,562	20,520
Research and development expenses	208	221	398	429
Selling, general and administrative expenses	422	485	870	967
Amortization of intangibles	104	118	220	236
Restructuring and asset related charges - net	65	40	221	127
Integration and separation costs	348	262	800	486
Equity in earnings (losses) of nonconsolidated affiliates	(15)	193	(29)	394
Interest income	21	18	39	38
Interest expense and amortization of debt discount	237	261	478	523
Income from continuing operations before income taxes	215	1,059	512	2,210
Provision for income taxes on continuing operations	125	249	266	475
Income from continuing operations, net of tax	90	810	246	1,735
Income from discontinued operations, net of tax	0	554	445	1,068
Net income	90	1,364	691	2,803
Net income attributable to noncontrolling interests	15	31	60	66
Net income available for Dow Inc. common stockholders	$ 75	$ 1,333	$ 631	$ 2,737
Earnings per common share from continuing operations - basic	$ 0.10	$ 1.05	$ 0.26	$ 2.26
Earnings per common share from discontinued operations - basic	0.00	0.73	0.58	1.40
Earnings per common share - basic	0.10	1.78	0.84	3.66
Earnings per common share from continuing operations - diluted	0.10	1.05	0.26	2.26
Earnings per common share from discontinued operations - diluted	0.00	0.73	0.58	1.40
Earnings per common share - diluted	$ 0.10	$ 1.78	$ 0.84	$ 3.66
Weighted-average common shares outstanding - basic	742.8	747.2	745.0	747.2
Weighted-average common shares outstanding - diluted	747.9	747.2	747.6	747.2
Depreciation	$ 538	$ 540	$ 1,081	$ 1,094
Capital expenditures	$ 470	$ 489	$ 912	$ 868