Earnings Per Share of Common Stock (Earnings Per Share of Common Stock Reconciliation) (Details) (USD $) In Millions, except Share data in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Net income attributable to DuPont	$ 452	$ 367	$ 3,101	$ 2,655
Preferred dividends	(3)	(3)	(8)	(8)
Net income available to Dupont common stockholders	$ 449	$ 364	$ 3,093	$ 2,647
Weighted-average number of common shares - Basic	932,356	908,366	929,369	906,991
Dilutive effect of the company's employee compensation plans	11,129	10,134	13,443	7,996
Weighted average number of common shares - Diluted	943,485	918,500	942,812	914,987