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Related Party Transactions - Summary of Related Party Carrying Value of Investments In Advances (Detail) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Related Party Transaction [Line Items] |  |  |
Total investments in and advances |  | $ 57,722 | $ 34,391
SSGT III OP |  |  |
Related Party Transaction [Line Items] |  |  |
Receivables |  | 2,769 | 629
Total investments in and advances |  | 15,511 | 8,291
SSGT III OP | SSGT III Mezzanine Loan |  |  |
Related Party Transaction [Line Items] |  |  |
Debt |  | 0 | 4,000
SSGT III OP | SSGT III Bridge Loan |  |  |
Related Party Transaction [Line Items] |  |  |
Debt | [1] | 2,919 | 0
SSGT III OP | SSGT III Promissory Note |  |  |
Related Party Transaction [Line Items] |  |  |
Debt | [2] | 7,000 | 0
SSGT III OP | SSGT III OP Units and SSGT III SLP |  |  |
Related Party Transaction [Line Items] |  |  |
Equity |  | 2,823 | 3,662
SST VI |  |  |
Related Party Transaction [Line Items] |  |  |
Receivables |  | 13,929 | 5,861
Total investments in and advances |  | 42,211 | 26,099
SST VI | SST VI Note |  |  |
Related Party Transaction [Line Items] |  |  |
Debt |  | 23,000 | 15,000
SST VI | SST VI OP Units and SLP |  |  |
Related Party Transaction [Line Items] |  |  |
Equity |  | 728 | 1,932
SST VI | SST VI Series C Units |  |  |
Related Party Transaction [Line Items] |  |  |
Equity |  | $ 4,554 | $ 3,306
[1] | In January of 2025, SSGT III repaid in full the remaining outstanding principal balance of approximately $2.9 million on the SSGT III Bridge Loan, plus accrued interest.
[2] | In January of 2025, SSGT III repaid in full the $7.0 million previously outstanding on the SSGT III Promissory Note, plus accrued interest.

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