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Debt and Preferred Equity Investments - Schedule of Debt Investments with an Aggregate Weighted Average Current Yield (Details) - USD ($) | 1 Months Ended | 9 Months Ended | 21 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 31, 2023 | Sep. 30, 2024 | Sep. 30, 2024 | Dec. 31, 2023 | Dec. 31, 2022
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |
Mortgage loans on real estate, interest rate |  | 6.32% |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Carrying Value, Fixed Rate |  | $ 293,924,000 | $ 293,924,000 | $ 346,745,000 |
Carrying Value |  | 293,924,000 | 293,924,000 | 346,745,000 |
Allowance for loan loss |  | (13,520,000) | (13,520,000) | (13,520,000) | $ (6,630,000)
Mezzanine Loan Due June 2024 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Amount participated out |  | 12,000,000.0 | 12,000,000.0 |  |
Loan interest income | $ 0 |  |  |  |
Debt Investments in Mortgage Loans |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 8,099,000 | 8,099,000 |  |
Senior Financing |  | 804,021,000 | 804,021,000 |  |
Carrying Value |  | 159,450,000 | 159,450,000 | 218,745,000 |
Allowance for loan loss |  | (13,520,000) | (13,520,000) | (13,520,000) |
Total fixed rate |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 285,000,000 | 285,000,000 |  |
Carrying Value, Fixed Rate |  | 63,366,000 | 63,366,000 | 63,366,000 |
Total fixed rate | Mezzanine Loan Due June 2024 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 105,000,000 | 105,000,000 |  |
Carrying Value, Fixed Rate |  | 13,366,000 | 13,366,000 | 13,366,000 |
Total fixed rate | Mezzanine Loan, with an Initial Maturity Date of January 2025 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 95,000,000 | 95,000,000 |  |
Carrying Value, Fixed Rate |  | 30,000,000 | 30,000,000 | 30,000,000 |
Total fixed rate | Mezzanine Loan With Initial Maturity Date of December 2029 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 85,000,000 | 85,000,000 |  |
Carrying Value, Fixed Rate |  | 20,000,000 | 20,000,000 | 20,000,000 |
Total floating rate |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 8,099,000 | 8,099,000 |  |
Senior Financing |  | 519,021,000 | 519,021,000 |  |
Carrying Value |  | 109,604,000 | 109,604,000 | 168,899,000 |
Total floating rate | Mezzanine Loan Due April 2023 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 275,000,000 | 275,000,000 |  |
Carrying Value |  | 50,000,000 | 50,000,000 | 50,000,000 |
Loan interest income |  |  | 0 |  |
Total floating rate | Mezzanine Loan Due May 2024 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 54,000,000 | 54,000,000 |  |
Carrying Value |  | 8,620,000 | 8,620,000 | 8,243,000 |
Total floating rate | Mezzanine Loan Due May 2024 One |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 8,099,000 | 8,099,000 |  |
Senior Financing |  | 190,021,000 | 190,021,000 |  |
Carrying Value |  | 50,984,000 | 50,984,000 | 48,323,000 |
Total floating rate | Mezzanine Loan Due January 2026 |  |  |  |  |
Debt Investments Held [Abstract] |  |  |  |  |
Future Funding Obligations |  | 0 | 0 |  |
Senior Financing |  | 0 | 0 |  |
Carrying Value |  | $ 0 | $ 0 | $ 62,333,000 |

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