Noncontrolling Interest, Consideration Transferred

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- Definition

Real Estate Properties, Ownership Interest Acquired By Noncontrolling Interest

+ References

No definition available.

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- Definition

Real Estate Property, Ownership Interest Sold

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- Definition

Real Estate Property, Ownership Interest Sold By Noncontrolling Interests

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- Definition

Temporary Equity, Contribution From Noncontrolling Interests

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No definition available.

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- Definition

Total Value Of Assets Acquired

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
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- Definition

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

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The value of an asset or business acquired in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

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

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- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

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- Definition

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Consolidated and unconsolidated real estate joint ventures (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2023 USD ($) ft²	Mar. 31, 2023 USD ($) ft²	Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Apr. 11, 2023
Schedule of Equity Method Investments
Area of Real Estate Property \| ft²			73,500,000
Contributions from and sales of noncontrolling interests			$ 547,391	$ 1,542,347	$ 2,026,486
Contributions from and sales of noncontrolling interests			542,589	1,560,129	2,147,061
Purchase Price			265,750	2,877,861	5,434,652
Contribution of assets from real estate joint venture partner			$ 33,250	19,146	118,750
1655 and 1715 Third Street
Schedule of Equity Method Investments
Equity interest percentage (in percent)			10.00%
1401/1413 Research Boulevard
Schedule of Equity Method Investments
Equity interest percentage (in percent)			65.00%
1450 Research Boulevard
Schedule of Equity Method Investments
Equity interest percentage (in percent)			73.20%
101 West Dickman Street
Schedule of Equity Method Investments
Equity interest percentage (in percent)			57.90%
50 and 60 Binney Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			34.00%
75/125 Binney Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			40.00%
100 and 225 Binney Street and 300 Third Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			30.00%
99 Coolidge Avenue \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			75.00%
15 Necco Street
Schedule of Equity Method Investments
Area of Real Estate Property \| ft²	345,996
Contributions from and sales of noncontrolling interests	$ 66,108
15 Necco Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent		90.00%	56.70%			72.00%
Other - Greater Boston
Schedule of Equity Method Investments
Purchase Price		$ 58,900
Total Value of Assets Acquired		37,600
Contribution of assets from real estate joint venture partner		$ 33,300
Other - Greater Boston \| Development Entitlements Acquired
Schedule of Equity Method Investments
Area of Real Estate Property \| ft²		515,000
Other - Greater Boston \| Future development
Schedule of Equity Method Investments
Area of Real Estate Property \| ft²		715,000
Other - Greater Boston \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			61.20%
Alexandria Center for Science and Technology - Mission Bay \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			25.00%
1450 Owens Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			40.60%
601, 611, 651, 681, 685, and 701 Gateway Boulevard \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			50.00%
751 Gateway Boulevard \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			51.00%
211 and 213 East Grand Avenue \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			30.00%
500 Forbes Boulevard \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			10.00%
Alexandria Center for Life Science – Millbrae \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			47.10%
3215 Merryfield Row \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			30.00%
Campus Point by Alexandria \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			55.00%
5200 Illumina Way \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			51.00%
9625 Towne Centre Drive
Schedule of Equity Method Investments
Area of Real Estate Property \| ft²	163,648
Contributions from and sales of noncontrolling interests	$ 32,261
Noncontrolling Interest, Consideration Transferred	$ 160,500
9625 Towne Centre Drive \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent		50.10%	30.00%
SD Tech by Alexandria \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			50.00%
Pacific Technology Park \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			50.00%
Summers Ridge Science Park \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			30.00%
1201 and 1208 Eastlake Avenue East and 199 East Blaine Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			30.00%
400 Dexter Avenue North \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			30.00%
800 Mercer Street \| Alexandria
Schedule of Equity Method Investments
Noncontrolling interest, ownership percentage by parent			60.00%
Noncontrolling Interests
Schedule of Equity Method Investments
Contributions from and sales of noncontrolling interests			$ 508,693	910,506	1,157,668
Noncontrolling Interests \| 15 Necco Street \| Alexandria
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners		10.00%
Real Estate Property, Ownership Interest Sold	18.00%
Noncontrolling Interests \| 15 Necco Street \| Alexandria \| New Partner
Schedule of Equity Method Investments
Real Estate Properties, Ownership Interest Acquired by Noncontrolling Interest	20.00%
Noncontrolling Interests \| 15 Necco Street \| Alexandria \| New Partner \| Minimum
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners						20.00%
Noncontrolling Interests \| 15 Necco Street \| Alexandria \| New Partner \| Maximum
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners	37.00%
Noncontrolling Interests \| 15 Necco Street \| Alexandria \| Existing Partner
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners						8.00%
Real Estate Property, Ownership Interest Sold by Noncontrolling Interests	2.00%
Noncontrolling Interests \| Other - Greater Boston \| Alexandria
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners		38.80%
Noncontrolling Interests \| 1450 Owens Street \| Alexandria
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners			75.00%
Noncontrolling Interests \| 9625 Towne Centre Drive \| Alexandria
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners		49.90%
Real Estate Property, Ownership Interest Sold	20.10%
Noncontrolling Interests \| 9625 Towne Centre Drive \| Alexandria \| New Partner
Schedule of Equity Method Investments
Ownership percentage by noncontrolling owners	70.00%
Noncontrolling Interests \| 9625 Towne Centre Drive \| Alexandria \| Previous Partner
Schedule of Equity Method Investments
Real Estate Property, Ownership Interest Sold by Noncontrolling Interests	49.90%
Additional Paid-In Capital
Schedule of Equity Method Investments
Contributions from and sales of noncontrolling interests			$ 33,896	649,623	989,393
Additional Paid-In Capital \| 15 Necco Street
Schedule of Equity Method Investments
Contributions from and sales of noncontrolling interests	$ (7,761)
Additional Paid-In Capital \| 9625 Towne Centre Drive
Schedule of Equity Method Investments
Contributions from and sales of noncontrolling interests	$ 15,553
Redeemable Noncontrolling Interests
Schedule of Equity Method Investments
Contributions from and sales of noncontrolling interests			$ 35,250	$ 0	$ 282
Redeemable Noncontrolling Interests \| Other - Greater Boston
Schedule of Equity Method Investments
Contributions from and sales of noncontrolling interests		$ 35,300