Condensed Consolidated Statements of Comprehensive Income (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	$ 25,641	$ 34,311	$ 58,416	$ 66,936
Unrealized gains (losses) on marketable securities:
Unrealized holding (losses) gains arising during the period	(107)	(501)	567	12
Reclassification adjustment for losses (gains) included in net income	238		(686)
Unrealized gains (losses) on marketable securities, net	131	(501)	(119)	12
Unrealized gains (losses) on interest rate swaps:
Unrealized interest rate swap losses arising during the period	(3,091)	(5,555)	(7,164)	(5,255)
Reclassification adjustment for amortization of interest expense included in net income	5,895	5,302	11,670	10,741
Unrealized gains (losses) on interest rate swap agreements, net	2,804	(253)	4,506	5,486
Foreign currency translation (losses) gains	(17,192)	1,676	(7,233)	6,559
Total other comprehensive (loss) income	(14,257)	922	(2,846)	12,057
Comprehensive income	11,384	35,233	55,570	78,993
Less: comprehensive income attributable to noncontrolling interests	(875)	(939)	(1,574)	(1,861)
Comprehensive income attributable to Alexandria Real Estate Equities, Inc.'s common stockholders	$ 10,509	$ 34,294	$ 53,996	$ 77,132