Commitments [Abstract]

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Concentration of credit risk [Abstract]

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Limited Partnership Maximum Expiration Terms

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Represents the number of largest tenants.

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Represents the number of leases held by the entity.

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Represents the number of tenants.

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Represents the expected period of payment obligation.

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Represents the remaining aggregate costs under contracts for the construction of properties undergoing development and redevelopment and generic life science laboratory infrastructure improvements contracts under the terms of leases.

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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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No definition available.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

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Amount of cost for defined contribution plan.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Remaining period of expected liquidation by investee of underlying asset of investment measured at net asset value per share or unit. In 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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Commitments and contingencies (Details) property in Thousands, Lease in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) property	Dec. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) Lease	Dec. 31, 2022 USD ($) Tenant	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Concentration Risk [Line Items]
Discretionary profit sharing contributions subject to statutory limitations			$ 8.7				$ 5.0	$ 6.2
Concentration of credit risk
Number of leases held \| Lease				1
Number of client tenants		1			1,000
Commitments
Remaining aggregate costs under contracts, under terms of leases	$ 3,500.0	$ 3,500.0	3,500.0	$ 3,500.0	$ 3,500.0	$ 3,500.0
Letters of credit and performance obligations	22.4	22.4	22.4	22.4	22.4	22.4
Investment commitments	$ 415.4	$ 415.4	$ 415.4	$ 415.4	$ 415.4	$ 415.4
Limited Partnership Maximum Expiration Terms	12 years
Weighted-average remaining liquidation term (in years)	5 years 4 months 24 days
Minimum
Commitments
Expected period of payment obligation	1 year
Maximum
Commitments
Expected period of payment obligation	3 years
Three Largest Tenants \| Lessee Concentration \| Annualized Base Rent
Concentration of credit risk
Number of largest tenants \| Tenant					3
Concentration risk, percentage						8.60%
First Largest Tenant \| Lessee Concentration \| Annualized Base Rent
Concentration of credit risk
Concentration risk, percentage						3.50%
Second Largest Tenant \| Lessee Concentration \| Annualized Base Rent
Concentration of credit risk
Concentration risk, percentage						2.60%
Third Largest Tenant \| Lessee Concentration \| Annualized Base Rent
Concentration of credit risk
Concentration risk, percentage						2.50%
Investments in privately held entities that report NAV
Commitments
Weighted-average remaining liquidation term (in years)	8 years 7 months 6 days