Earnings Per Share (Details) - USD ($)	3 Months Ended
	Oct. 31, 2015	Nov. 01, 2014
Earnings Per Share [Abstract]
Net income attributable to Ecology and Environment, Inc.	$ 664,093	$ 847,160
Dividends declared	0	0
Balance at end of period	$ 664,093	$ 847,160
Weighted-average common shares outstanding (basic and diluted) (in shares)	4,288,404	4,288,371
Distributed earnings per share (in dollars per share)	$ 0	$ 0
Undistributed earnings per share (in dollars per share)	0.15	0.20
Total earnings per share (in dollars per share)	$ 0.15	$ 0.20
Minimum percentage right of Class B common stock holders to elect Board of Directors	75.00%