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Loss Contingency, Cure Period

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Loss Contingency, Estimate of Possible Loss, Range, Daily Lower Limit

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Loss Contingency, Estimate Of Possible Loss, Range, Daily Upper Limit

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Potential Asset Disposition, Consideration

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Real Estate Property, Ownership Interest Sold

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Reversal Of Impairment Charges

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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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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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The number of real estate properties owned as of the balance sheet date.

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The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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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 - Sale of Real Estate Assets and Impairment of Real Estate (Details) $ in Thousands		1 Months Ended		3 Months Ended				9 Months Ended		10 Months Ended
	Apr. 10, 2026 USD ($)	Oct. 26, 2026 USD ($) ft²	Dec. 31, 2025 USD ($)	Sep. 30, 2026 USD ($) ft² property	Jun. 30, 2026 USD ($) property	Dec. 31, 2025 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) ft² property	Sep. 30, 2025 USD ($)	Oct. 26, 2026 USD ($) ft²
Real Estate Properties
Proceeds from sales of real estate								$ 7,350
Impairment of real estate				$ 637,904			$ 323,870	865,873	$ 485,630
Gain on sales of real estate				0			$ 9,366	$ 0	$ 22,531
Cure period								30 days
Daily possible loss, lower limit				1				$ 1
Daily possible loss, upper limit				$ 2				$ 2
H+H and EDC Litigation
Real Estate Properties
Security deposit	$ 5,000
Estimate of possible loss	$ 3,800
North America
Real Estate Properties
Area of real estate property \| ft²				36,500,000				36,500,000
Proceeds from sales of real estate								$ 241,750
Number of real estate properties \| property				328				328
Gross investments in real estate			$ 34,103,488	$ 34,366,769		$ 34,103,488		$ 34,366,769
North America \| Subsequent Event
Real Estate Properties
Proceeds from sales of real estate										$ 716,750
3825 and 3875 Fabian Way
Real Estate Properties
Real Estate Property, Ownership Interest Sold				100.00%				100.00%
Proceeds from sales of real estate								$ 163,000
Impairment of real estate			144,700
Potential Asset Disposition, Consideration					$ 163,000
Gain on sales of real estate				$ 0
Reversal Of Impairment Charges					(23,300)
3825 and 3875 Fabian Way \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				228,000				228,000
3825 and 3875 Fabian Way \| Future Development Projects
Real Estate Properties
Area of real estate property \| ft²				250,000				250,000
One Hampshire Street
Real Estate Properties
Real Estate Property, Ownership Interest Sold				100.00%				100.00%
Proceeds from sales of real estate								$ 44,900
Impairment of real estate			105,700		24,800
Potential Asset Disposition, Consideration					43,700
Gain on sales of real estate				$ 0
One Hampshire Street \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				104,956				104,956
One Hampshire Street \| Future Development Projects
Real Estate Properties
Area of real estate property \| ft²				0				0
3911/3931/4025/4031/4045/4075 Sorrento Valley Blvd
Real Estate Properties
Real Estate Property, Ownership Interest Sold				100.00%				100.00%
Proceeds from sales of real estate								$ 26,500
Impairment of real estate					28,200
Potential Asset Disposition, Consideration					$ 26,700
Gain on sales of real estate				$ 0
3911/3931/4025/4031/4045/4075 Sorrento Valley Blvd \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				95,814				95,814
Number of real estate properties \| property					5
3911/3931/4025/4031/4045/4075 Sorrento Valley Blvd \| Future Development Projects
Real Estate Properties
Area of real estate property \| ft²				144,000				144,000
3911/3931/4025/4031/4045/4075 Sorrento Valley Blvd \| Land
Real Estate Properties
Area of real estate property \| ft²				144,000				144,000
Campus Point by Alexandria \| Subsequent Event
Real Estate Properties
Proceeds from sales of real estate		$ 475,000
Campus Point by Alexandria \| Operating Properties \| Subsequent Event
Real Estate Properties
Area of real estate property \| ft²		1,586,697								1,586,697
Campus Point by Alexandria \| Future Development Projects \| Subsequent Event
Real Estate Properties
Area of real estate property \| ft²		366,816								366,816
421 Park Drive
Real Estate Properties
Area of real estate property \| ft²				339,668				339,668
Impairment of real estate				$ 343,300
Potential Asset Disposition, Consideration				$ 238,900
421 Park Drive \| Future Development Projects
Real Estate Properties
Area of real estate property \| ft²				392,011				392,011
Number of real estate properties \| property				1				1
San Diego Market
Real Estate Properties
Impairment of real estate					$ 64,200
Potential Asset Disposition, Consideration					43,300
San Diego Market \| Land
Real Estate Properties
Area of real estate property \| ft²				425,000				425,000
11045 Roselle Street
Real Estate Properties
Impairment of real estate				$ 9,400
Potential Asset Disposition, Consideration				$ 10,900
11045 Roselle Street \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				27,689				27,689
Number of real estate properties \| property				1				1
Sorrento Mesa and Sorrento Valley Properties
Real Estate Properties
Impairment of real estate				$ 8,500	4,200
Potential Asset Disposition, Consideration				$ 54,700
Sorrento Mesa and Sorrento Valley Properties \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				157,449				157,449
Number of real estate properties \| property				4				4
88 Bluxome Street
Real Estate Properties
Impairment of real estate			$ 333,400		29,300
Potential Asset Disposition, Consideration					$ 41,800
88 Bluxome Street \| Future Development Projects
Real Estate Properties
Area of real estate property \| ft²				1,100,000				1,100,000
3301, 3301, 3305, and 3307 Hillview Avenue
Real Estate Properties
Impairment of real estate				$ 135,300
Potential Asset Disposition, Consideration				$ 95,300
3301, 3301, 3305, and 3307 Hillview Avenue \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				292,746				292,746
Number of real estate properties \| property				4				4
1501-1599 Industrial Road
Real Estate Properties
Impairment of real estate				$ 79,200
Potential Asset Disposition, Consideration				$ 39,400
1501-1599 Industrial Road \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				103,325				103,325
Number of real estate properties \| property				6				6
2100, 2200, 2300, and 2400 Geng Road
Real Estate Properties
Impairment of real estate				$ 41,600
Potential Asset Disposition, Consideration				$ 124,200
2100, 2200, 2300, and 2400 Geng Road \| Future Development Projects
Real Estate Properties
Area of real estate property \| ft²				240,000				240,000
Number of real estate properties \| property				1				1
6000 and 6200 Middle Fiskville
Real Estate Properties
Impairment of real estate				$ 50,400
Potential Asset Disposition, Consideration				$ 11,100
6000 and 6200 Middle Fiskville \| Land
Real Estate Properties
Area of real estate property \| ft²				344,000				344,000
720 Bay Street
Real Estate Properties
Impairment of real estate								$ 55,000
Potential Asset Disposition, Consideration								$ 42,500
720 Bay Street \| Operating Properties
Real Estate Properties
Area of real estate property \| ft²				247,743				247,743
Montreal properties
Real Estate Properties
Impairment of real estate						$ 107,100		$ 27,800
Potential Asset Disposition, Consideration								134,500
Montreal properties & 720 Bay Street
Real Estate Properties
Reversal Of Impairment Charges				$ (31,500)
Alexandria Center for Life Science - New York City
Real Estate Properties
Gross investments in real estate				$ 185,900				$ 185,900