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Debt and Preferred Equity Investments - Schedule of Activity in Debt and Preferred Equity Investments (Details) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 USD ($) investment | Dec. 31, 2023 USD ($) investment
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Balance at beginning of period | $ 346,745 | $ 623,280
Redemptions/sales/syndications/equity ownership/amortization | (64,629) | (349,947)
Net change in loan loss reserves | 0 | (6,890)
Balance at end of period | $ 293,924 | $ 346,745
Number of investments, nonperforming | investment | 2 | 2
Carrying Value | $ 293,924 | $ 346,745
Preferred Equity (4) |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Carrying Value | 134,474 |
Preferred Equity (4) | 625 Madison Avenue |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Carrying Value | 209,900 |
Total floating rate |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Carrying Value | 109,604 | 168,899
Alternative Strategy Portfolio (3) | Total floating rate |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Carrying Value | 49,800 |
Debt Investment |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Originations/Accretion | 5,334 | 72,160
Preferred Equity Investments |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] |  |
Originations/Accretion | $ 6,474 | $ 8,142

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- Definition Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 948 -SubTopic 310 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29(Column G)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1 + Details
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