Net income attributable to Alexandria Real Estate Equities, Inc. (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net income attributable to Alexandria Real Estate Equities, Inc.:
Income from continuing operations	$ 25,435	$ 33,974	$ 56,211	$ 66,287
Gain on sale of land parcel			1,864
Less: net income attributable to noncontrolling interests	(851)	(938)	(1,562)	(1,867)
Income from continuing operations attributable to Alexandria Real Estate Equities, Inc.	24,584	33,036	56,513	64,420
Income from discontinued operations attributable to Alexandria Real Estate Equities, Inc., net	206	337	341	649
Net income attributable to Alexandria Real Estate Equities, Inc.	$ 24,790	$ 33,373	$ 56,854	$ 65,069