Consolidated Statemets of Income (USD $)	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Consolidated Statemets of Income [Abstract]
Revenue	$ 155,410,099	$ 169,172,860	$ 144,098,294
Cost of professional services and other direct operating expenses	55,632,281	65,914,987	49,623,816
Subcontract costs	32,315,179	31,325,937	30,292,117
Administrative and indirect operating expenses	44,917,631	42,534,303	38,166,067
Marketing and related costs	15,601,112	15,251,165	14,438,785
Depreciation and amortization	2,160,062	1,760,763	1,684,406
Income from operations	4,783,834	12,385,705	9,893,103
Interest expense	(364,305)	(355,766)	(222,558)
Interest income	174,743	85,771	107,211
Other income (expense)	206,813	64,524	(68,349)
Gain on sale of assets	0	290,526	809,200
Net foreign currency exchange gain (loss)	(403,419)	284,411	(59,718)
Income before income tax provision	4,397,666	12,755,171	10,458,889
Income tax provision (benefit)	1,357,916	4,631,235	3,902,222
Net income	3,039,750	8,123,936	6,556,667
Net income attributable to noncontrolling interests	(2,266,171)	(1,163,673)	(2,299,060)
Net income attributable to Ecology and Environment, Inc.	$ 773,579	$ 6,960,263	$ 4,257,607
Net income per common share: basic and diluted (in dollars per share)	$ 0.18	$ 1.65	$ 1.02
Weighted average common shares outstanding: basic and diluted (in shares)	4,233,883	4,222,688	4,160,816