Document And Entity Information (USD $)	12 Months Ended
	Jul. 31, 2012	Jan. 31, 2012
Entity Registrant Name	ECOLOGY & ENVIRONMENT INC
Entity Central Index Key	0000809933
Current Fiscal Year End Date	--07-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Public Float	$ 42,638,845
Entity Common Stock, Shares Outstanding		4,243,917
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY
Document Type	10-K
Amendment Flag	true
Amendment Description	Filing to include Interactive Data
Document Period End Date	Jul. 31, 2012