Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023 USD ($) tenant lease	Sep. 30, 2023 USD ($) tenant segment lease	Dec. 31, 2022 USD ($)
Accounting Policies [Line Items]
Cash in excess of FDIC insured amounts	$ 5.3	$ 5.3	$ 27.1
Straight-line rent receivables	$ 62.7	$ 62.7	53.9
Accounts Receivable, Allowance for Credit Loss, Number Of Leases \| lease	4	4
Accounts Receivable, Allowance for Credit Loss, Number Of Customers \| tenant	4	4
Increase to rental income	$ 0.3	$ 0.2
Allowance for doubtful accounts receivable (in dollars)	0.0	$ 0.0	0.0
Number of Reportable Segments \| segment		1
Unbilled Revenues [Member]
Accounting Policies [Line Items]
Accounts Receivable, Gross	$ 14.7	$ 14.7	$ 11.1
Building [Member]
Accounting Policies [Line Items]
Useful life	40 years	40 years
Building Improvements [Member] \| Minimum
Accounting Policies [Line Items]
Useful life	10 years	10 years
Building Improvements [Member] \| Maximum
Accounting Policies [Line Items]
Useful life	20 years	20 years

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Number of customers related to the total allowance for credit loss on accounts receivable.

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The increase (decrease) during the reporting period in the rental income due to uncollectible charges.

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Amount of right to consideration from customer for renting of property in normal course of business.

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount of allowance for credit loss on accounts receivable.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
-Section S99
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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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