Condensed consolidating financial information Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Assets
Investments in real estate, net	$ 7,774,608	$ 7,629,922
Investments in and advances to affiliates	132,433	127,212
Cash and cash equivalents	256,000	125,098	$ 68,617	$ 86,011
Restricted cash	13,131	28,872
Tenant receivables	9,196	10,485
Deferred rent	303,379	280,570
Deferred leasing costs	191,619	192,081
Investments	360,050	353,465
Investments in and Advances to Affiliates, Balance, Principal Amount	0	0
Other assets	104,414	133,312
Total assets	9,144,830	8,881,017
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	722,794	809,818
Unsecured senior notes payable	2,376,713	2,030,631
Unsecured senior line of credit	72,000	151,000
Unsecured senior bank term loans	945,030	944,243
Accounts payable, accrued expenses, and tenant security deposits	593,628	589,356
Dividends payable	67,188	62,005
Total liabilities	4,777,353	4,587,053
Redeemable noncontrolling interests	9,218	14,218
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	4,021,709	3,975,087
Noncontrolling interests	336,550	304,659
Total equity	4,358,259	4,279,746
Total liabilities, noncontrolling interests, and equity	9,144,830	8,881,017
Eliminations
Assets
Investments in real estate, net	0	0
Investments in and advances to affiliates	0	0
Cash and cash equivalents	0	0	0	0
Restricted cash	0	0
Tenant receivables	0	0
Deferred rent	0	0
Deferred leasing costs	0	0
Investments	0	0
Investments in and Advances to Affiliates, Balance, Principal Amount	(14,276,712)	(13,816,222)
Other assets	0	0
Total assets	(14,276,712)	(13,816,222)
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	0	0
Unsecured senior notes payable	0	0
Unsecured senior line of credit	0	0
Unsecured senior bank term loans	0	0
Accounts payable, accrued expenses, and tenant security deposits	0	0
Dividends payable	0	0
Total liabilities	0	0
Redeemable noncontrolling interests	0	0
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	(14,276,712)	(13,816,222)
Noncontrolling interests	0	0
Total equity	(14,276,712)	(13,816,222)
Total liabilities, noncontrolling interests, and equity	(14,276,712)	(13,816,222)
Alexandria Real Estate Equities, Inc. (Issuer)
Assets
Investments in real estate, net	0	0
Investments in and advances to affiliates	0	0
Cash and cash equivalents	140,569	31,982	35,230	52,491
Restricted cash	94	91
Tenant receivables	0	0
Deferred rent	0	0
Deferred leasing costs	0	0
Investments	0	0
Investments in and Advances to Affiliates, Balance, Principal Amount	7,423,205	7,194,092
Other assets	35,855	36,808
Total assets	7,599,723	7,262,973
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	0	0
Unsecured senior notes payable	2,376,713	2,030,631
Unsecured senior line of credit	72,000	151,000
Unsecured senior bank term loans	945,030	944,243
Accounts payable, accrued expenses, and tenant security deposits	117,369	100,294
Dividends payable	66,902	61,718
Total liabilities	3,578,014	3,287,886
Redeemable noncontrolling interests	0	0
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	4,021,709	3,975,087
Noncontrolling interests	0	0
Total equity	4,021,709	3,975,087
Total liabilities, noncontrolling interests, and equity	7,599,723	7,262,973
Alexandria Real Estate Equities, L.P. (Guarantor Subsidiary)
Assets
Investments in real estate, net	0	0
Investments in and advances to affiliates	0	0
Cash and cash equivalents	0	0	0	63
Restricted cash	0	0
Tenant receivables	0	0
Deferred rent	0	0
Deferred leasing costs	0	0
Investments	4,766	4,702
Investments in and Advances to Affiliates, Balance, Principal Amount	6,716,778	6,490,009
Other assets	0	0
Total assets	6,721,544	6,494,711
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	0	0
Unsecured senior notes payable	0	0
Unsecured senior line of credit	0	0
Unsecured senior bank term loans	0	0
Accounts payable, accrued expenses, and tenant security deposits	0	0
Dividends payable	0	0
Total liabilities	0	0
Redeemable noncontrolling interests	0	0
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	6,721,544	6,494,711
Noncontrolling interests	0	0
Total equity	6,721,544	6,494,711
Total liabilities, noncontrolling interests, and equity	6,721,544	6,494,711
Combined Non- Guarantor Subsidiaries
Assets
Investments in real estate, net	7,774,608	7,629,922
Investments in and advances to affiliates	132,433	127,212
Cash and cash equivalents	115,431	93,116	$ 33,387	$ 33,457
Restricted cash	13,037	28,781
Tenant receivables	9,196	10,485
Deferred rent	303,379	280,570
Deferred leasing costs	191,619	192,081
Investments	355,284	348,763
Investments in and Advances to Affiliates, Balance, Principal Amount	136,729	132,121
Other assets	68,559	96,504
Total assets	9,100,275	8,939,555
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	722,794	809,818
Unsecured senior notes payable	0	0
Unsecured senior line of credit	0	0
Unsecured senior bank term loans	0	0
Accounts payable, accrued expenses, and tenant security deposits	476,259	489,062
Dividends payable	286	287
Total liabilities	1,199,339	1,299,167
Redeemable noncontrolling interests	9,218	14,218
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	7,555,168	7,321,511
Noncontrolling interests	336,550	304,659
Total equity	7,891,718	7,626,170
Total liabilities, noncontrolling interests, and equity	$ 9,100,275	$ 8,939,555