Stock-Based Compensation Restricted Stock Units and Performance Deferred Stock (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended		2 Months Ended		3 Months Ended	4 Months Ended	7 Months Ended		8 Months Ended	12 Months Ended
		Nov. 30, 2017	Aug. 31, 2019	Nov. 30, 2017	May 31, 2019		Mar. 31, 2019	Dec. 31, 2017	Dec. 31, 2019		Aug. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	May 31, 2019	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												3 years
Weighted Average Grant Date Fair Value, RSUs and PSUs granted during the period											$ 91.56
Remaining Weighted-Average Recognition Period												1 year
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, equity instruments other than options, actual awards granted, percentage of performance target		0.00%	0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, equity instruments other than options, actual awards granted, percentage of performance target		200.00%	200.00%
RSUs and PSUs - OIP [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested RSUs and PSUs at beginning of period	[1]								3,757,000
RSUs and PSUs granted during the period									2,228,000
RSUs and PSUs vested during the period									(497,000)
RSUs and PSUs forfeited during the period									(50,000)
Nonvested RSUs and PSUs at end of period									5,438,000			5,438,000
Weighted average grant date fair value, nonvested RSUs and PSUs beginning of period	[1]								$ 35.56
Weighted Average Grant Date Fair Value, RSUs and PSUs granted during the period									28.88			$ 28.88
Weighted Average Grant Date Fair Value, vested RSUs and PSUs during the period									39.07
Weighted Average Grant Date Fair Value, RSUs and PSUs forfeited during the period									36.50
Weighted average grant date fair value, nonvested RSUs and PSUs end of period									$ 35.56	[1]		$ 32.49
Fair Value of RSUs and PSUs vested during the period												$ 19
Unrecognized Pretax Compensation Expense Related to RSUs and PSUs												$ 57
RSUs and PSUs - EIP [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested RSUs and PSUs at beginning of period					6,120,000	[2]	3,147,000					3,147,000
RSUs and PSUs granted during the period					1,288,000	[3]	2,578,000
RSUs and PSUs vested during the period					(76,000)		(1,113,000)
RSUs and PSUs forfeited during the period					(47,000)		(12,000)
Nonvested RSUs and PSUs at end of period					3,100,000		4,600,000						3,147,000
Weighted average grant date fair value, nonvested RSUs and PSUs beginning of period					$ 39.46	[2]	$ 68.18					$ 68.18
Weighted Average Grant Date Fair Value, RSUs and PSUs granted during the period					42.34	[3]	52.66
Weighted Average Grant Date Fair Value, vested RSUs and PSUs during the period					42.26		67.85
Weighted Average Grant Date Fair Value, RSUs and PSUs forfeited during the period					40.35		67.08
Weighted average grant date fair value, nonvested RSUs and PSUs end of period					$ 39.46	[2]	$ 68.18					$ 68.18	$ 68.18	$ 40.18	$ 59.57
Fair Value of RSUs and PSUs vested during the period								$ 9			$ 84	$ 79	$ 128
Remaining Weighted-Average Recognition Period												1 year
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity award conversion ratio												1
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU Requisite Service Period												6 months
Restricted Stock Units and Performance Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Grant Date Fair Value, RSUs and PSUs granted during the period			$ 29.02	$ 71.16				$ 70.02			$ 76.41	$ 52.19	$ 70.37
Internal Reorganization [Member] | RSUs and PSUs - EIP [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Impact of Internal Reorganizations					(4,185,000)
Impact of Internal Reorganizations, Weighted Average Grant Date Fair Value					$ 39.76
Corteva [Member] | RSUs and PSUs - EIP [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion - Corteva Distribution	[4]													(3,100,000)
Conversion - Corteva Distribution, weighted average grant date fair value														$ 40.18
Minimum [Member] | Management [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												3 years
Maximum [Member] | Management [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												5 years
OIP [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												3 years
EIP [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												3 years
Dow [Member] | Minimum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												1 year
Dow [Member] | Maximum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU and PSU Award Vesting Period												3 years

[1] As a result of the Corteva Distribution, all outstanding DowDuPont equity awards under the EIP were converted into Corteva-denominated awards under the “Employer Method,” or into DuPont-denominated awards under the “Shareholder Method,” using a formula designed to preserve the intrinsic value of the awards immediately prior to and subsequent to the Corteva Distribution and moved to the OIP.

[2] As a result of the Dow Distribution, all outstanding DowDuPont equity awards under the EIP were converted into DowDuPont-denominated awards under the “Employer Method,” or into Dow-denominated awards under the “Shareholder Method,” using a formula designed to preserve the intrinsic value of the awards immediately prior to and subsequent to the Dow Distribution.

[3] As a result of the Dow Distribution, outstanding DowDuPont equity awards under the Heritage Dow Plans were moved to the EIP and were converted into DowDuPont-denominated awards under the “Employer Method,” or into Dow-denominated awards under the “Shareholder Method,” using a formula designed to preserve the intrinsic value of the awards immediately prior to and subsequent to the Dow Distribution. These outstanding equity awards are included in the number of “Granted” awards in the table above.

[4] As a result of the Corteva Distribution, all outstanding DowDuPont equity awards under the EIP were converted into Corteva-denominated awards under the “Employer Method,” or into DuPont-denominated awards under the “Shareholder Method,” using a formula designed to preserve the intrinsic value of the awards immediately prior to and subsequent to the Corteva Distribution and moved to the OIP.