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	Mar. 31, 2024 USD ($) investment	Dec. 31, 2023 USD ($) investment
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	0
2022	0
Prior	352,347
Carrying value	$ 352,347	$ 346,745
Number of investments, nonperforming \| investment	2	2
Carrying Value	$ 352,347	$ 346,745
Total floating rate
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	172,386	168,899
Alternative Strategy Portfolio \| 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	214,740
Carrying value	214,740	210,333
2 - Watch List Assets - Higher potential for loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	137,607
Carrying value	137,607	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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
-Paragraph 5
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

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- Definition

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

+ References

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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.

+ References

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

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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