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Equity Incentive Plans - Additional information (Details) - USD ($) | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Jun. 28, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Stock-based compensation | $ 3,300,000 | $ 2,500,000 | $ 9,800,000 | $ 10,600,000 |  |  |
Unrecognized compensation costs | $ 21,300,000 | $ 16,000,000 | $ 21,300,000 | $ 16,000,000 |  |  |
Total unrecognized compensation costs expected to be recognized, period |  |  | 2 years 9 months 18 days | 1 year 9 months 18 days |  |  |
Performance award shares vested (in shares) |  |  | 526,292 | 578,579 |  |  |
Unvested performance awards (in shares) | 1,735,389 | 1,066,693 | 1,735,389 | 1,066,693 | 958,985 | 1,037,848 |
Minimum |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting percentages |  |  | 0.00% |  |  |  |
Maximum |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting percentages |  |  | 200.00% |  |  |  |
Employee Stock Option |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Stock-based compensation |  |  | $ 73,000 | $ 52,000 |  |  |
Service vesting awards granted |  |  | $ 134,000 | 143,000 |  |  |
Service-Vesting Awards |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting awards |  |  | 2 years |  |  |  |
Service vesting awards granted |  |  | $ 18,300,000 | $ 11,100,000 |  |  |
Service-Vesting Awards | Share-Based Payment Arrangement, Tranche One |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting percentages |  |  | 33.33% |  |  |  |
Service-Vesting Awards | Share-Based Payment Arrangement, Tranche Two |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting percentages |  |  | 33.33% |  |  |  |
Service-Vesting Awards | Share-Based Payment Arrangement, Tranche Three |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting percentages |  |  | 33.33% |  |  |  |
Performance Vesting Awards |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Service vesting awards |  |  | The total compensation will be determined by the Company’s TSR relative to specified BDCs during a specified performance period. Depending on the results achieved during the specified performance period, the actual number of shares that a grant recipient receives at the end of the period may range from 0% to 200% of the target shares granted. |  |  |  |
Vesting period |  |  | 4 years |  |  |  |
Performance award shares vested (in shares) |  |  | 0 |  |  |  |
Unvested performance awards (in shares) | 0 | 0 | 0 | 0 |  |  |
Performance Vesting Awards | Minimum |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Disposal period after vesting |  |  | 1 year |  |  |  |
Performance Vesting Award |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Performance award shares vested (in shares) |  |  |  | 487,409 |  |  |
Performance DEUs |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Performance award shares vested (in shares) |  |  | 54,858 | 241,770 |  |  |
Distribution equivalent units (“DEUs”) were issued with a grant date fair value |  |  | $ 700,000 | $ 4,000,000 |  |  |
Liability Classified Awards |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Stock-based compensation |  |  | 1,100,000 | 2,300,000 |  |  |
Unrecognized compensation costs | $ 900,000 | $ 2,300,000 | $ 900,000 | $ 2,300,000 |  |  |
Total unrecognized compensation costs expected to be recognized, period |  |  | 7 months 6 days | 1 year 7 months 6 days |  |  |
Vesting period |  |  | 4 years |  |  |  |
Remaining max award value | $ 3,100,000 |  | $ 3,100,000 |  |  |  |
Weighted average performance conditions in liability | 100.00% |  | 100.00% |  |  |  |
Accounts payable and accrued liabilities | $ 2,200,000 | $ 2,000,000 | $ 2,200,000 | $ 2,000,000 |  |  |
Liability award vested |  |  | $ 0 | $ 6,000,000 |  |  |
Other Liability Classified Awards |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  | 3 years |  |  |  |
2018 Plan | Restricted Stock |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  | 9,261,229
Director Plan | Restricted Stock |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  | 300,000
2018 and Direct Plan |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  | 18,700,000
2018 and Direct Plan | Restricted Stock |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  | 300,000

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