Stockholders' Equity Common Stock (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Apr. 30, 2020	Dec. 31, 2019	Jun. 26, 2019	Jun. 01, 2019
Class of Stock [Line Items]
Common Stock, Par Value	$ 0.01		$ 0.01	$ 0.01
Common Stock, Shares, Outstanding, Beginning Balance	748,577,000
Common Stock, Shares, Outstanding, Ending Balance	748,369,000
Stock Repurchase Program, Authorized Amount					$ 1,000
Payments for Repurchase of Common Stock	$ 50	$ 0
Corteva [Member]
Class of Stock [Line Items]
Common Stock, Shares, Issued						748,815,000
Common Stock, Par Value	$ 0.01				$ 0.01	$ 0.01
Common Stock, Shares, Outstanding, Beginning Balance	748,577,000
Common Stock, Shares, Issued	1,657,000
Stock Repurchased and Retired During Period, Shares	(1,865,000)
Common Stock, Shares, Outstanding, Ending Balance	748,369,000
Payments for Repurchase of Common Stock	$ 50
Corteva [Member] | Shares of Corteva Stock [Member]
Class of Stock [Line Items]
Exchange Ratio						1
Corteva [Member] | Shares of DowDuPont Common Stock Held [Member]
Class of Stock [Line Items]
Exchange Ratio						3