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v3.25.3

Commitments and Contingencies - Additional Information (Detail) | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2025 USD ($) loan | Sep. 30, 2025 USD ($) security_loan | Sep. 30, 2025 USD ($) | Sep. 30, 2025 USD ($) director | Dec. 31, 2024 USD ($) loan | Dec. 31, 2024 USD ($) security_loan | Sep. 30, 2024 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Current expected credit loss reserves for unfunded loan commitments | $ 13,741,000 | $ 13,741,000 | $ 13,741,000 | $ 13,741,000 | $ 13,741,000 | $ 10,412,000 | $ 10,412,000 | $ 8,300,000
Number of loans |  | 137 | 137 |  |  | 130 | 130 |
Number of non-employee directors eligible for annual compensation | director |  |  |  |  | 6 |  |  |
Number of directors not eligible for compensation | director |  |  |  |  | 2 |  |  |
Board of Directors |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Annual cash compensation |  |  |  | 210,000 |  |  |  |
Annual cash compensation paid in cash |  |  |  | 95,000 |  |  |  |
Annual cash compensation paid in the form of deferred stock units |  |  |  | 115,000 |  |  |  |
Annual cash compensation |  |  |  | 30,000 |  |  |  |
Audit Committee |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Annual cash compensation |  |  |  | 20,000 |  |  |  |
Compensation Committee |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Annual cash compensation |  |  |  | 15,000 |  |  |  |
Corporate Governance Committee |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Annual cash compensation |  |  |  | 10,000 |  |  |  |
Audit Committee Members |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Annual cash compensation |  |  |  | 10,000 |  |  |  |
Investment risk management committee |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Annual cash compensation |  |  |  | 7,500 |  |  |  |
Unfunded Loan Commitment |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Current expected credit loss reserves for unfunded loan commitments | 1,532,429,000 | $ 1,532,429,000 | $ 1,532,429,000 | 1,532,429,000 | $ 1,532,429,000 | $ 1,263,068,000 | $ 1,263,068,000 |
Number of loans | loan |  | 57 |  |  |  |  |  |
Aggregate unfunded loan commitments | 800,100,000 | $ 800,100,000 | 800,100,000 | 800,100,000 | 800,100,000 |  |  |
Net unfunded commitments | $ 732,300,000 | $ 732,300,000 | $ 732,300,000 | $ 732,300,000 | $ 732,300,000 |  |  |
Weighted-average future funding period (in years) | 2 years 1 month 6 days |  |  |  |  |  |  |

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