Number Of Properties Impaired

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Proceeds from sale of real estate assets and partial interest

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Real Estate Property, Ownership Interest Sold

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Area of a real estate property.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of increase in noncontrolling interest from sale of a portion of the parent's controlling interest.

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Amount of cash inflow from a noncontrolling interest. Includes, but is not limited to, purchase of additional shares or other increase in noncontrolling interest ownership.

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Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Investments in real estate - Real estate asset sales (Details) $ in Thousands	3 Months Ended			12 Months Ended
	Sep. 30, 2022 USD ($) ft²	Jun. 30, 2022 USD ($) ft²	Mar. 31, 2022 USD ($) ft²	Dec. 31, 2022 USD ($) ft² property	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jul. 01, 2022
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²				74,600,000
Proceeds from sale of real estate assets and partial interest	$ 960,386	$ 548,682		$ 2,200,000
Proceeds from Noncontrolling Interests				1,542,347	$ 2,026,486	$ 367,613
Gain on sales of real estate	323,699	$ 214,219		537,918	126,570	154,089
Contributions from and sales of noncontrolling interests				1,560,129	2,147,061	717,158
Impairment of real estate				64,969	52,675	48,078
Noncontrolling Interests
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests				910,506	1,157,668	449,726
Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests				$ 649,623	$ 989,393	$ 267,432
100 Binney Street
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²			432,931
Proceeds from Noncontrolling Interests			$ 713,228
100 Binney Street \| Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests			$ 413,615
300 Third Street
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²		131,963
Proceeds from Noncontrolling Interests		$ 166,485
300 Third Street \| Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests		$ 113,020
Alexandria Park at 128, 285 Bear Hill Road, 111 and 130 Forbes Blvd, and 20 Walkup Drive
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²		617,043
Real Estate Property, Ownership Interest Sold		100.00%
Proceeds from sale of real estate		$ 334,397
Gain on sales of real estate		202,325
Other
Real Estate Properties [Line Items]
Proceeds from sale of real estate	182,696	47,800
Gain on sales of real estate	65,109	$ 11,894
1450 Owens Street
Real Estate Properties [Line Items]
Proceeds from Noncontrolling Interests	25,039
1450 Owens Street \| Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests	$ 10,083
341 and 343 Oyster Point Boulevard, 7000 Shoreline Court, and 75 and 125 Shoreway Road
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²	330,379
Real Estate Property, Ownership Interest Sold	100.00%
Proceeds from sale of real estate	$ 383,635
Gain on sales of real estate	$ 223,127
3215 Merryfield Row
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²	170,523
Proceeds from Noncontrolling Interests	$ 149,940
3215 Merryfield Row \| Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests	$ 42,214
Summers Ridge Science Park
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²	316,531
Proceeds from Noncontrolling Interests	$ 159,600
Summers Ridge Science Park \| Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests	$ 65,097
7330 and 7360 Carroll Road
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²	84,442
Real Estate Property, Ownership Interest Sold	100.00%
Proceeds from sale of real estate	$ 59,476
Gain on sales of real estate	$ 35,463
Alexandria \| 100 Binney Street \| Noncontrolling Interests
Real Estate Properties [Line Items]
Ownership percentage by noncontrolling owners			70.00%
Alexandria \| 300 Third Street \| Noncontrolling Interests
Real Estate Properties [Line Items]
Ownership percentage by noncontrolling owners		70.00%
Alexandria \| 1450 Owens Street \| Noncontrolling Interests
Real Estate Properties [Line Items]
Ownership percentage by noncontrolling owners				75.00%
Real Estate Property, Ownership Interest Sold							20.00%
Alexandria \| 3215 Merryfield Row \| Noncontrolling Interests
Real Estate Properties [Line Items]
Ownership percentage by noncontrolling owners	70.00%
Alexandria \| Summers Ridge Science Park \| Noncontrolling Interests
Real Estate Properties [Line Items]
Ownership percentage by noncontrolling owners	70.00%
Future development \| 1450 Owens Street
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²	191,000
North America
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²				41,800,000
Proceeds from sale of real estate assets and partial interest				$ 2,222,296
Proceeds from sale of real estate				1,000,000
Proceeds from Noncontrolling Interests				1,200,000
Impairment of real estate				44,100
North America \| Additional Paid-In Capital
Real Estate Properties [Line Items]
Contributions from and sales of noncontrolling interests	$ 117,394	$ 113,020		$ 644,029
North America \| Future development
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²				6,665,029
San Francisco Bay Area
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²				600,000
Impairment of real estate		$ 38,300
San Francisco Bay Area \| Future development
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²				610,000
Other markets
Real Estate Properties [Line Items]
Impairment of real estate				$ 20,900
Number of properties impaired \| property				10
Other markets \| Future development
Real Estate Properties [Line Items]
Area of Real Estate Property \| ft²				1,644,994