Stockholders' Equity Common Stock (Details) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares		Oct. 29, 2020 $ / shares	Dec. 31, 2019 $ / shares	Jun. 26, 2019 USD ($) $ / shares	Jun. 01, 2019 shares $ / shares
Class of Stock [Line Items]
Common Stock, Par Value | $ / shares	$ 0.01	$ 0.01	$ 0.01	$ 0.01		$ 0.01	$ 0.01
Common Stock, Shares, Outstanding, Beginning Balance			748,577,000
Common Stock, Shares, Outstanding, Ending Balance	747,492,000	748,390,000	747,492,000	748,390,000
Stock Repurchase Program, Authorized Amount | $								$ 1,000
Repurchase of Common Stock | $	$ 33	$ 25	$ 83	$ 25	[1]
Corteva [Member]
Class of Stock [Line Items]
Common Stock, Shares, Issued									748,815,000
Common Stock, Par Value | $ / shares	$ 0.01		$ 0.01					$ 0.01	$ 0.01
Common Stock, Shares, Outstanding, Beginning Balance			748,577,000
Common Stock, Shares, Issued			1,940,000
Stock Repurchased and Retired During Period, Shares	1,160,000	824,000	(3,025,000)
Common Stock, Shares, Outstanding, Ending Balance	747,492,000		747,492,000
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

[1] The cash flows for the nine months ended September 30, 2019 includes cash flows of EID's ECP and Specialty Products Entities.