Restructuring and Asset Related Charges DowDuPont Cost Synergy Program (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		34 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		$ 179	$ 60	$ 249	$ 121
DowDuPont Cost Synergy Program [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance				69
Restructuring and Asset Related Charges - Net		0	60	(3)	122	$ 842
Payments for Restructuring				(14)
Restructuring Reserve, Ending Balance		55		55		55
DowDuPont Cost Synergy Program [Member] | Severance and Related Benefit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance				29
Restructuring and Asset Related Charges - Net		0	0	0	14	319
Payments for Restructuring				(13)
Restructuring Reserve, Ending Balance		16		16		16
DowDuPont Cost Synergy Program [Member] | Costs Associated with Exit and Disposal Activities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance	[1]			40
Restructuring and Asset Related Charges - Net		0	49	0	69	193
Payments for Restructuring	[1]			(1)
Restructuring Reserve, Ending Balance	[1]	39		39		39
DowDuPont Cost Synergy Program [Member] | Asset Related Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		0	11	(3)	39	$ 330
DowDuPont Cost Synergy Program [Member] | Seed [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		(3)	49	(6)	73
DowDuPont Cost Synergy Program [Member] | Crop Protection [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		3	2	3	29
DowDuPont Cost Synergy Program [Member] | Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		$ 0	$ 9	$ 0	$ 20

[1] Relates primarily to contract terminations charges.