Earnings Per Share Net Income for Earnings Per Share Calculations - Basic and Diluted (Details) - USD ($) $ in Millions	3 Months Ended															12 Months Ended
	Dec. 31, 2020	[1]	Sep. 30, 2020	Jun. 30, 2020	[2]	Mar. 31, 2020	[3],[4]	Dec. 31, 2019	[5]	Sep. 30, 2019	[6],[7]	Jun. 30, 2019	[8]	Mar. 31, 2019	[9]	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations After Taxes	$ 99		$ (390)	$ 766		$ 281		$ (42)		$ (527)		$ 483		$ (184)		$ 756	$ (270)	$ (6,775)
Income (loss) from continuing operations attributable to Corteva common stockholders																736	(283)	(6,804)
(Loss) income from discontinued operations after income taxes																(55)	(671)	1,748
Loss from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest																0	5	9
(Loss) income from discontinued operations attributable to Corteva common stockholders																(55)	(676)	1,739
Net (Loss) Income attributable to common stockholders																681	(959)	(5,065)
Net Income attributable to continuing operations - Noncontrolling Interest																$ 20	$ 13	$ 29

[1] Fourth quarter 2020 includes an after-tax benefit of $(182) million related to Swiss Tax Reform. See Note 10 - Income Taxes, to the Consolidated Financial Statements, for additional information.

[2] Second quarter 2020 includes an after-tax benefit of $(29) million due to an elective change in accounting method that alters the 2019 impact of the business separation on the 2017 Tax Cuts and Jobs Act's foreign tax provision. See Note 10 - Income Taxes, to the Consolidated Financial Statements for additional information.

[3] First quarter 2020 includes a $19 million after tax charge related to the impact of a state tax valuation allowance in the U.S. based on a change in judgment about the realizability of a deferred tax asset. See Note 10 - Income Taxes, to the Consolidated Financial Statements, for additional information.

[4] First quarter 2020 includes a loss of $(53) million recorded in other income - net related to the expected sale of the La Porte site, for which the company signed an agreement during the first quarter 2020.

[5] Fourth quarter 2019 includes a tax benefit of $(34) million related to the impact of the release of a tax valuation allowance recorded against the net deferred tax asset position of a Switzerland legal entity. See Note 10 - Income Taxes, to the Consolidated Financial Statements for additional information.

[6] Third quarter 2019 includes a $33 million charge included in other income (expense) - net associated with remeasuring the company’s Argentine Peso net monetary assets, resulting from an unexpected August primary election result in Argentina. 

[7] Third quarter 2019 includes a tax benefit of $(38) million related to Swiss Tax Reform. See Note 10 - Income Taxes, to the Consolidated Financial Statements for additional information.

[8] Includes a loss on early extinguishment of debt of $(13) million in the second quarter of 2019 related to the retirement of some of the company's debt. See Note 17 - Long-Term Debt and Available Credit Facilities, to the Consolidated Financial Statements for additional information.

[9] First quarter 2019 includes a $(24) million loss recorded in other income (expense) - net related to Historical Dow’s sale of a joint venture related to synergy actions.