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Equity Based Compensation - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Feb. 28, 2023 | Feb. 28, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Unrecognized compensation expense related to non-vested equity awards |  |  | $ 7,900,000 |  | $ 7,900,000 |  |  | $ 4,800,000 | $ 4,500,000 |
Unrecognized compensation expense, expected weighted average-recognition period |  |  |  |  | 2 years 4 months 24 days |  |  | 2 years 1 month 6 days | 2 years 1 month 6 days |
Property Operating Expenses |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Share based compensation expense |  |  |  |  |  |  |  | $ 155,000 | $ 80,000 | $ 40,000
Property operating expenses and Managed REIT Platform expenses |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Share based compensation expense |  |  | 100,000 | $ 100,000 | $ 400,000 |  | $ 400,000 |  |  |
General and Administrative Expense |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Share based compensation expense |  |  | $ 1,300,000 | $ 800,000 | $ 3,700,000 |  | $ 2,700,000 | $ 3,800,000 | $ 2,800,000 | $ 1,600,000
Time Based Awards | Restricted Stock Awards |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  | 3 years |  |  | 3 years |  |
Unvested Shares, Granted |  |  |  |  | 43,720 |  |  | 60,032 | 78,192 |
Time Based Awards | LTIP Units |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Unvested Shares, Granted |  |  |  |  | 315,915 |  |  | 181,664 | 222,581 |
Time Based Awards | LTIP Units | Executive Officers |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  | 4 years |  |  |  |  |  |  |  |
Unvested Shares, Granted | 275,308 |  |  |  |  |  |  |  |  |
Performance Based Awards |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Awards vesting date |  |  |  |  | Mar. 31, 2024 |  |  |  |  | Mar. 31, 2023
Awards vesting year |  |  |  |  | Mar. 31, 2025 |  | Mar. 31, 2026 | Mar. 31, 2025 | Mar. 31, 2024 |
Performance Based Awards | Restricted Stock Awards |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of established target performance criteria |  |  |  |  | 100.00% |  |  | 100.00% |  |
Share based compensation arrangement by share based payment award voting rights |  |  |  |  | do not have |  |  |  |  |
Unvested Shares, Granted |  |  |  |  | 5,752 | [1] |  | 0 |  |
Performance Based Awards | LTIP Units |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of established target performance criteria |  |  |  |  | 200.00% |  |  | 200.00% |  |
Description of distribution and allocation of profits and losses |  |  |  |  | Recipients of performance based restricted stock accrue distributions during the performance period, and such distributions will only be payable on the date that any such shares of restricted stock vest, based upon the performance level attained. Recipients of performance based LTIP Units are issued LTIP Units at 200% of the targeted award and are entitled to receive distributions and allocations of profits and losses with respect to the performance based LTIP Units as of the effective date of each award in an amount equal to 10% of the distributions and allocations available to such LTIP Units, until the Distribution Participation Date (as defined in the Operating Partnership Agreement). The remaining 90% of distributions will accrue and will be payable on the Distribution Participation Date based upon the performance level attained and number of performance based LTIP Units that vest. |  |  | Recipients of performance based LTIP Units are issued LTIP Units at 200% of the targeted award and are entitled to receive distributions and allocations of profits and losses with respect to the performance based LTIP Units as of the effective date of each award in an amount equal to 10% of the distributions and allocations available to such LTIP Units, until the Distribution Participation Date (as defined in the Operating Partnership Agreement). The remaining 90% of distributions will accrue and will be payable on the Distribution Participation Date based upon the performance level attained and number of performance based LTIP Units that vest. |  |
Share based compensation arrangement by share based payment award voting rights |  |  |  |  | one vote per LTIP Unit |  |  |  |  |
Unvested Shares, Granted |  |  |  |  | 271,199 |  |  | 113,429 | 148,387 |
Performance Based Awards | LTIP Units | Executive Officers |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Unvested Shares, Granted | 271,199 |  |  |  |  |  |  |  |  |
Employee and Director Long-term Incentive Plan |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Shares available for issuance |  |  | 9,367,118 |  | 9,367,118 |  |  | 9,978,272 |  |
Minimum | Time Based Awards | Restricted Stock Awards |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  | 1 year |  |  | 1 year |  |
Minimum | Performance Based Awards | Restricted Stock Awards |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of established target performance criteria |  |  |  |  | 0.00% |  |  | 0.00% |  |
Maximum | Time Based Awards | Restricted Stock Awards |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  | 4 years |  |  | 4 years |  |
Maximum | Performance Based Awards | LTIP Units |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of established target performance criteria |  |  |  |  | 200.00% |  |  | 200.00% |  |
[1] | On March 2, 2023 the Compensation Committee of the board of directors approved the vesting of the 2020 performance grant at 200% of the targeted award. Accordingly, individuals who elected to receive performance based restricted stock were issued and immediately vested additional shares to equal 200% of their targeted award.

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