Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Consolidated Statements of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 2,953	$ 608	$ 4,200
Foreign currency translation adjustments	230	(557)	(2,152)
Unrealized investment (losses) gains, net	(18)	21	(4)
Comprehensive income	3,165	72	2,044
Comprehensive (income) loss attributable to noncontrolling interests	(25)	397	(192)
Comprehensive income attributable to Ecology and Environment, Inc.	$ 3,140	$ 469	$ 1,852

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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