Consolidated Statemets of Income (USD $)	3 Months Ended		6 Months Ended
	Jan. 31, 2012	Jan. 29, 2011	Jan. 31, 2012	Jan. 29, 2011
Consolidated Statemets of Income [Abstract]
Revenue	$ 40,173,399	$ 41,833,006	$ 82,485,205	$ 84,004,584
Cost of professional services and other direct operating expenses	12,769,082	16,904,362	28,346,785	33,141,683
Subcontract costs	9,587,945	7,941,444	18,700,085	15,169,362
Administrative and indirect operating expenses	11,630,073	10,062,846	22,829,327	20,448,064
Marketing and related costs	3,883,727	3,294,379	7,826,007	7,173,147
Depreciation and amortization	435,202	426,214	876,039	860,098
Income from operations	1,867,370	3,203,761	3,906,962	7,212,230
Interest expense	(83,676)	(90,053)	(163,976)	(171,872)
Interest income	20,184	49,006	31,866	75,197
Other income (expense)	11,245	(14,613)	120,523	(8,183)
Gain on sale of assets	0	58,332	0	58,332
Net foreign exchange gain (loss)	(130,181)	31,421	(126,849)	13,014
Income before income tax provision	1,684,942	3,237,854	3,768,526	7,178,718
Income tax provision	381,867	1,113,457	1,060,184	2,579,952
Net income	1,303,075	2,124,397	2,708,342	4,598,766
Net income attributable to noncontrolling interests	(799,571)	(366,385)	(1,045,061)	(982,179)
Net income attributable to Ecology and Environment, Inc.	$ 503,504	$ 1,758,012	$ 1,663,281	$ 3,616,587
Net income per common share: basic and diluted (in dollars per share)	$ 0.12	$ 0.42	$ 0.39	$ 0.86
Weighted average common shares outstanding: basic and diluted (in shares)	4,242,108	4,228,957	4,222,776	4,215,687