Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Consolidated Statements of Operations [Abstract]
Gross revenue	$ 90,684	$ 96,083	$ 98,248
Cost of professional services and other direct operating expenses	33,855	36,179	36,436
Subcontract costs	17,191	15,975	17,106
Selling, general and administrative expenses	39,257	38,139	40,970
Depreciation and amortization	1,083	994	1,042
(Loss) income from operations	(702)	4,796	2,694
Income from equity method investment	595	368	363
Interest income (expense)	114	29	(55)
Net foreign exchange (loss) gain	(11)	(86)	44
Proxy contest costs, net	0	(375)	0
Gain on insurance settlement	0	0	358
Other income (expense)	158	(54)	(104)
Income before income tax provision	154	4,678	3,300
Income tax provision	258	2,167	3,146
Net (loss) income	(104)	2,511	154
Net (income) loss attributable to noncontrolling interests	(204)	312	587
Net (loss) income attributable to Ecology and Environment Inc.	$ (308)	$ 2,823	$ 741
Net (loss) income per common share: basic and diluted (in dollars per share)	$ (0.07)	$ 0.66	$ 0.17
Weighted average common shares outstanding: basic and diluted (in shares)	4,304,574	4,294,501	4,289,993