Segment Reporting Segment Information (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2021		Sep. 30, 2020		Sep. 30, 2021		Sep. 30, 2020		Dec. 31, 2020
Segment Reporting Information [Line Items]
Net Sales	$ 2,371		$ 1,863		$ 12,176		$ 11,010
Segment operating EBITDA	(11)		(152)		2,420		1,932
Segment Assets	36,240		36,965		36,240		36,965		$ 36,850
Seed [Member]
Segment Reporting Information [Line Items]
Net Sales	738		523		7,010		6,516
Segment operating EBITDA	(217)		(282)		1,523		1,255
Segment Assets	23,701	[1]	24,372	[1]	23,701	[1]	24,372	[1]	23,751
Crop Protection [Member]
Segment Reporting Information [Line Items]
Net Sales	1,633		1,340		5,166		4,494
Segment operating EBITDA	206		130		897		677
Segment Assets	$ 12,539	[1]	$ 12,593	[1]	$ 12,539	[1]	$ 12,593	[1]	$ 13,099

[1] Segment assets at December 31, 2020 were $23,751 million and $13,099 million for Seed and Crop Protection, respectively.