Earnings Per Share of Common Stock (Earnings Per Share of Common Stock Reconciliation) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net income attributable to DuPont	$ 1,488	$ 1,431
Preferred dividends	(3)	(3)
Net income available to common stockholders	$ 1,485	$ 1,428
Weighted-average number of common shares - Basic	933,910	924,897
Dilutive effect of the company's employee compensation plans	10,328	16,012
Weighted average number of common shares outstanding - Diluted	944,238	940,909