Supplementary Information Other Income (Expense) - Net (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Interest income		$ 13	$ 12	$ 46	$ 63
Equity in losses of affiliates - net		(3)	(3)	(8)	(2)
Net gain (loss) on sales of businesses and other assets		2	1	(9)	35
Net exchange (losses) gains	[1]	(11)	(74)	(70)	(190)	[2]
Non-operating pension and other post employment benefit credit	[3]	47	67	144	204
Miscellaneous income (expenses) - net	[4]	11	4	(13)	8
Other income - net		59	7	90	118
Hedging Program [Member]
Net exchange (losses) gains		55	31	(11)	27	[5]
Argentine peso devaluation [Member] | Hedging Program [Member]
Net exchange (losses) gains		$ (42)	$ (40)	$ (33)	(73)
Tax Reform Foreign Currency Exchange Impact [Member] | Hedging Program [Member]
Net exchange (losses) gains					$ (50)

[1] Includes net pre-tax exchange losses of $(33) million and $(42) million for the three and nine months ended September 30, 2019, respectively and $(40) million and $(73) million for the three and nine months ended September 30, 2018, respectively, associated with the devaluation of the Argentine peso.

[2] Includes a $(50) million foreign exchange loss for the nine months ended September 30, 2018 related to adjustments to foreign currency exchange contracts as a result of U.S. tax reform, which is included within significant items.

[3] Includes non-service related components of net periodic benefit credits (costs) (interest cost, expected return on plan assets, amortization of unrecognized (gain) loss, amortization of prior service benefit and curtailment/settlement loss).

[4] Miscellaneous income (expenses) - net, includes losses from sale of receivables, tax indemnification adjustments related to changes in indemnification balances as a result of the application of the terms of the Tax Matters Agreement, between Corteva and Dow and/or DuPont, and other items. Refer to Note 12 - Accounts and Notes Receivable - Net, for additional information on losses on the sale of receivables.

[5] Includes a $(50) million foreign exchange loss for the nine months ended September 30, 2018 related to adjustments to foreign currency exchange contracts as a result of U.S. tax reform.