Condensed Consolidated Statement of Changes in Stockholders' Equity and Noncontrolling Interests (USD $) In Thousands, except Share data	Total	Total Equity	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests.	Series C	Series C Preferred Stock	Series D Convertible	Series D Convertible Preferred Stock	Redeemable Noncontrolling Interests
Balance at Dec. 31, 2010	$ 2,970,408	$ 2,970,408	$ 550	$ 2,566,238	$ 734	$ (18,335)	$ 41,583		$ 129,638		$ 250,000	$ 15,920
Balance (in shares) at Dec. 31, 2010			54,966,925
Increase (Decrease) in Stockholders' Equity
Net income	66,936	66,359			65,069		1,290					577
Unrealized gain on marketable securities	12	12				12
Unrealized gain on interest rate hedge agreements	5,486	5,486				5,486
Foreign currency translation	6,559	6,535				6,565	(30)					24
Distributions to noncontrolling interests		(1,468)					(1,468)					(622)
Equity component related to repurchase of unsecured convertible notes (see Note 6)		(2,451)		(2,451)
Issuances of common stock, net of offering costs		451,539	63	451,476
Issuances of common stock, net of offering costs (in shares)			6,250,651
Issuances pursuant to stock plan		10,566	1	10,565
Issuances pursuant to stock plan (in shares)			162,692
Dividends declared on preferred stock		(14,178)			(14,178)
Dividends declared on common stock		(52,850)			(52,850)
Distributions in excess of earnings				(1,225)	1,225
Comprehensive income (loss)	78,993
Comprehensive income attributable to noncontrolling interests	1,861
Comprehensive income (loss) attributable to Alexandria Real Estate Equities, Inc.	77,132
Balance at Jun. 30, 2011	3,439,958	3,439,958	614	3,024,603		(6,272)	41,375		129,638		250,000	15,899
Balance (in shares) at Jun. 30, 2011			61,380,268
Balance at May. 31, 2011
Increase (Decrease) in Stockholders' Equity
Dividends declared on preferred stock								(2,700)		(4,400)
Dividends declared on common stock	(27,900)
Balance at Jun. 30, 2011	$ 3,439,958								$ 129,638		$ 250,000