Condensed consolidating financial information Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Assets
Investments in real estate, net	$ 6,930,262	$ 6,776,914
Cash and cash equivalents	74,970	57,696	87,001	140,971
Restricted cash	30,454	27,709
Tenant receivables	10,619	9,918
Deferred rent	202,087	190,425
Deferred leasing and financing costs, net	192,618	192,658
Investments	169,322	140,288
Investments in and advances to affiliates	0	0
Other assets	145,707	134,156
Total assets	7,756,039	7,529,764
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	597,511	708,831
Unsecured senior notes payable	1,048,270	1,048,230
Unsecured senior line of credit	506,000	204,000
Unsecured senior bank term loans	1,100,000	1,100,000
Accounts payable, accrued expenses, and tenant security deposits	443,893	435,342
Dividends payable	55,860	54,420
Total liabilities	3,751,534	3,550,823
Redeemable noncontrolling interests	14,413	14,444
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	3,922,736	3,916,789
Noncontrolling interests	67,356	47,708
Total equity	3,990,092	3,964,497
Total liabilities, noncontrolling interests, and equity	7,756,039	7,529,764
Alexandria Real Estate Equities, Inc. (Issuer)
Assets
Investments in real estate, net	0	0
Cash and cash equivalents	36,379	14,790	39,012	98,567
Restricted cash	54	55
Tenant receivables	0	0
Deferred rent	0	0
Deferred leasing and financing costs, net	35,051	36,901
Investments	0	0
Investments in and advances to affiliates	6,601,258	6,299,551
Other assets	18,755	20,226
Total assets	6,691,497	6,371,523
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	0	0
Unsecured senior notes payable	1,048,270	1,048,230
Unsecured senior line of credit	506,000	204,000
Unsecured senior bank term loans	1,100,000	1,100,000
Accounts payable, accrued expenses, and tenant security deposits	58,921	48,373
Dividends payable	55,570	54,131
Total liabilities	2,768,761	2,454,734
Redeemable noncontrolling interests	0	0
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	3,922,736	3,916,789
Noncontrolling interests	0	0
Total equity	3,922,736	3,916,789
Total liabilities, noncontrolling interests, and equity	6,691,497	6,371,523
Alexandria Real Estate Equities, L.P. (Guarantor Subsidiary)
Assets
Investments in real estate, net	0	0
Cash and cash equivalents	0	0	0	1,914
Restricted cash	0	0
Tenant receivables	0	0
Deferred rent	0	0
Deferred leasing and financing costs, net	0	0
Investments	10,868	10,868
Investments in and advances to affiliates	6,090,900	5,823,058
Other assets	0	0
Total assets	6,101,768	5,833,926
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	6,101,768	5,833,926
Noncontrolling interests	0	0
Total equity	6,101,768	5,833,926
Total liabilities, noncontrolling interests, and equity	6,101,768	5,833,926
Combined Non- Guarantor Subsidiaries
Assets
Investments in real estate, net	6,930,262	6,776,914
Cash and cash equivalents	38,591	42,906	47,989	40,490
Restricted cash	30,400	27,654
Tenant receivables	10,619	9,918
Deferred rent	202,087	190,425
Deferred leasing and financing costs, net	157,567	155,757
Investments	158,454	129,420
Investments in and advances to affiliates	124,891	119,421
Other assets	126,952	113,930
Total assets	7,779,823	7,566,345
Liabilities, Noncontrolling Interests, and Equity
Secured notes payable	597,511	708,831
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	384,972	386,969
Dividends payable	290	289
Total liabilities	982,773	1,096,089
Redeemable noncontrolling interests	14,413	14,444
Alexandria Real Estate Equities, Inc.’s stockholders’ equity	6,715,281	6,408,104
Noncontrolling interests	67,356	47,708
Total equity	6,782,637	6,455,812
Total liabilities, noncontrolling interests, and equity	7,779,823	7,566,345
Eliminations
Assets
Investments in real estate, net	0	0
Cash and cash equivalents	0	0	0	0
Restricted cash	0	0
Tenant receivables	0	0
Deferred rent	0	0
Deferred leasing and financing costs, net	0	0
Investments	0	0
Investments in and advances to affiliates	(12,817,049)	(12,242,030)
Other assets	0	0
Total assets	(12,817,049)	(12,242,030)
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	(12,817,049)	(12,242,030)
Noncontrolling interests	0	0
Total equity	(12,817,049)	(12,242,030)
Total liabilities, noncontrolling interests, and equity	$ (12,817,049)	$ (12,242,030)