Earnings Per Share (Details) (USD $)	3 Months Ended		6 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Earnings Per Share [Abstract]
Net (loss) income attributable to Ecology and Environment, Inc.	$ (152,331)	$ (784,648)	$ 694,829	$ (404,257)
Dividends declared	(1,033,071)	(1,033,551)	(1,033,071)	(1,033,551)
Balance at end of period	$ (1,185,402)	$ (1,818,199)	$ (338,242)	$ (1,437,808)
Weighted-average common shares outstanding (basic and diluted) (in shares)	4,288,371	4,290,193	4,288,371	4,278,694
Distributed earnings per share (in dollars per share)	$ 0.24	$ 0.24	$ 0.24	$ 0.24
Undistributed earnings per share (in dollars per share)	$ (0.28)	$ (0.42)	$ (0.08)	$ (0.33)
Total earnings per share (in dollars per share)	$ (0.04)	$ (0.18)	$ 0.16	$ (0.09)
Minimum percentage right of Class B common stock holders to elect Board of Directors (in hundredths)			75.00%