Commitments and Contingent Liabilities Environmental (Details) $ in Millions	Sep. 30, 2019 USD ($)
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 349	[1]
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	720
Indemnification Assets	204
Superfund Sites [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	51
Chemours [Member] | Indemnification Agreement [Member] | Superfund Sites [Member]
Loss Contingencies [Line Items]
Indemnification Assets	30
Chemours related obligation subject to indemnification [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	170	[2],[3]
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	383
Indemnification Assets	170
Discontinued Operations [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	102	[1],[2]
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	224
Indemnification Assets	0
Environmental remediation liabilities primarily related to DuPont - subject to indemnity from DuPont [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	34	[1]
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	61
Indemnification Assets	34
Not subject to indemnification [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	43	[1]
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	52
Indemnification Assets	0
DuPont de Nemours [Member] | DuPont de Nemours [Member]
Loss Contingencies [Line Items]
Stray liability threshold	$ 200

[1] Accrual balance represents management’s best estimate of the costs of remediation and restoration, although it is reasonably possible that the potential exposure, as indicated, could range above the amounts accrued, as there are inherent uncertainties in these estimates.

[2] Represents liabilities that are subject the $200 million thresholds and sharing arrangements as discussed on page 41, under Corteva Separation Agreement.

[3] The company has recorded an indemnification asset related to these accruals, including $30 million related to the Superfund sites.