Restructuring and Asset Related Charges DowDuPont Cost Synergy Program (Details) - USD ($) $ in Millions		3 Months Ended		31 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		$ 70	$ 61
DowDuPont Cost Synergy Program [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance		69
Restructuring and Asset Related Charges - Net		(3)	62	$ 842
Payments for Restructuring		(4)
Asset write-offs and adjustments		(2)
Restructuring Reserve, Ending Balance		63		63
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	14	319
Payments for Restructuring		(6)
Asset write-offs and adjustments		0
Restructuring Reserve, Ending Balance		23		23
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	20	193
Payments for Restructuring	[1]	0
Asset write-offs and adjustments	[1]	0
Restructuring Reserve, Ending Balance	[1]	40		40
DowDuPont Cost Synergy Program [Member] | Asset Related Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance		0
Restructuring and Asset Related Charges - Net		(3)	28	330
Payments for Restructuring		2
Asset write-offs and adjustments		(2)
Restructuring Reserve, Ending Balance		0		$ 0
DowDuPont Cost Synergy Program [Member] | Seed [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		(3)	24
DowDuPont Cost Synergy Program [Member] | Crop Protection [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		0	27
DowDuPont Cost Synergy Program [Member] | Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring and Asset Related Charges - Net		$ 0	$ 11

[1] Relates primarily to contract terminations charges.