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		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Income from continuing operations after income taxes attributable to DuPont	$ (43)	$ 368	$ 2,450	$ 2,830
Preferred dividends	(3)	(3)	(8)	(8)
Income from continuing operations after income taxes available to DuPont common stockholders	(46)	365	2,442	2,822
Income from discontinued operations after income taxes available to DuPont common stockholders	53	84	227	271
Net income available to common stockholders	$ 7	$ 449	$ 2,669	$ 3,093
Weighted-average number of common shares - Basic	931,737	932,356	933,227	929,369
Dilutive effect of the company's employee compensation plans	8,789	11,129	9,297	13,443
Weighted average number of common shares outstanding - Diluted	940,526	943,485	942,524	942,812