Debt and Preferred Equity Investments - Schedule of Carrying Value of Debt and Preferred Equity Investment Portfolio by Year of Origination and Risk Rating (Details) $ in Thousands	Sep. 30, 2024 USD ($) investment	Dec. 31, 2023 USD ($) investment
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	0
2022	0
Prior	293,924
Carrying value	$ 293,924	$ 346,745
Number of investments, nonperforming \| investment	2	2
Carrying Value	$ 293,924	$ 346,745
Total floating rate
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	109,604	168,899
Alternative Strategy Portfolio (3) \| Total floating rate
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	49,800
1 - Low Risk Assets - Low probability of loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	154,474
Carrying value	154,474	210,333
2 - Watch List Assets - Higher potential for loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	139,450
Carrying value	139,450	136,412
3 - High Risk Assets - Loss more likely than not
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	0
Carrying value	$ 0	$ 0

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease.

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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