Represents the amount of loans and leases receivable from related parties, net of the allowance for credit losses.

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Value of real estate assets including acquired real estate leases.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Indicates valuation technique for measuring investment in debt security at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of real estate investment property, net of accumulated depreciation, 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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- Definition

The gain (loss) recognized on initial consolidation of a variable interest entity (VIE) when the VIE is not a business (as defined).

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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.

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Organization, Properties, Basis of Presentation, Financial Instruments and Recent Accounting Standards - Variable Interest Entities (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jan. 01, 2023 USD ($)	Dec. 31, 2022 USD ($)
Variable interest entity
Gain on consolidation of Sponsored REIT		$ 394
Cash, cash equivalents and restricted cash		$ 6,697	$ 31,495	$ 127,880		$ 6,632
VIE at Consolidation
Real estate assets			840,756	890,824
Value of acquired real estate leases			5,306	6,694
Variable interest entities ("VIEs")
Variable interest entity
Gain on consolidation of Sponsored REIT	$ 400
Cash, cash equivalents and restricted cash			1,745	2,167
VIE at Consolidation
Real estate assets			19,184	19,354	$ 19,695
Value of acquired real estate leases			$ 67	$ 305	305
Total					20,000
Variable interest entities ("VIEs") \| FSP Monument Circle LLC
Variable interest entity
Cash, cash equivalents and restricted cash	$ 3,000
Variable interest entities ("VIEs") \| Level 3
VIE at Consolidation
Related party mortgage loan receivable					$ 20,000
Debt Securities, Available-for-Sale, Valuation Technique [Extensible Enumeration]					us-gaap:ValuationTechniqueDiscountedCashFlowMember
Variable interest entities ("VIEs") \| Level 3 \| Exit Cap Rate \| Minimum
VIE at Consolidation
Measurement input					7.50
Variable interest entities ("VIEs") \| Level 3 \| Exit Cap Rate \| Maximum
VIE at Consolidation
Measurement input					7.50
Variable interest entities ("VIEs") \| Level 3 \| Exit Cap Rate \| Weighted Average
VIE at Consolidation
Measurement input					7.50
Variable interest entities ("VIEs") \| Level 3 \| Discount Rate \| Minimum
VIE at Consolidation
Measurement input					9.50
Variable interest entities ("VIEs") \| Level 3 \| Discount Rate \| Maximum
VIE at Consolidation
Measurement input					9.50
Variable interest entities ("VIEs") \| Level 3 \| Discount Rate \| Weighted Average
VIE at Consolidation
Measurement input					9.50