Document and Entity Information	6 Months Ended
Jun. 30, 2011	Aug. 05, 2011
Document and Entity Information
Entity Registrant Name	ALEXANDRIA REAL ESTATE EQUITIES INC
Entity Central Index Key	0001035443
Document Type	10-Q
Document Period End Date	Jun. 30, 2011
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		61,932,136
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q2

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End date of current fiscal year in the format --MM-DD.

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