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Debt and Preferred Equity Investments - Narrative (Details) | 12 Months Ended | 41 Months Ended
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Dec. 31, 2023 USD ($) investment security segment | Dec. 31, 2022 USD ($) segment investment | Dec. 31, 2021 USD ($) | Dec. 31, 2023 USD ($) investment
Preferred equity investment |  |  |  |
Number of investments, nonperforming | investment | 2 | 1 |  | 2
Debt and preferred equity investments | $ 346,745,000 | $ 623,280,000 |  | $ 346,745,000
Recorded investment, past due | $ 346,745,000 | $ 623,280,000 |  | 346,745,000
Number of portfolio segments of financial receivables (segment) | segment | 1 | 1 |  |
Current period provision for loan loss | $ 6,890,000 | $ 0 | $ 2,931,000 |
Number financing receivable, nonaccrual status | security | 1 |  |  |
Financing receivable, nonaccrual status | $ 5,600,000 |  |  | 5,600,000
Loan interest income |  |  |  | 0
2 - Watch List Assets - Higher potential for loss |  |  |  |
Preferred equity investment |  |  |  |
Provision for loan loss recognized | 6,900,000 |  |  |
Recorded investment, past due | 136,412,000 | 352,321,000 |  | 136,412,000
Other Assets |  |  |  |
Preferred equity investment |  |  |  |
Total after allowance for loan loss | 8,800,000 | 9,000,000 |  | 8,800,000
Current period provision for loan loss | 0 | 0 |  |
Financing Receivables, Equal to Greater than 90 Days Past Due |  |  |  |
Preferred equity investment |  |  |  |
Recorded investment, past due | 0 | 0 |  | 0
Floating Rate |  |  |  |
Preferred equity investment |  |  |  |
Debt and preferred equity investments | 168,899,000 | 144,210,000 |  | 168,899,000
Mortgage Investment One | Floating Rate |  |  |  |
Preferred equity investment |  |  |  |
Debt and preferred equity investments |  | 6,900,000 |  |
Three Mortgage Investments | Floating Rate |  |  |  |
Preferred equity investment |  |  |  |
Debt and preferred equity investments | 49,800,000 |  |  | 49,800,000
Preferred Equity Investments |  |  |  |
Preferred equity investment |  |  |  |
Total after allowance for loan loss | $ 128,000,000 | $ 119,858,000 |  | $ 128,000,000

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