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Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock, Narrative (Details) $ in Thousands |  |  |  |  |  | 9 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jun. 17, 2022 | Mar. 18, 2022 | Jun. 17, 2021 shares | Apr. 01, 2021 shares | Mar. 18, 2021 independent_director shares | Sep. 30, 2021 USD ($) shares | Sep. 30, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Total unrecognized compensation expense | $ |  |  |  |  |  | $ 0 |
Restricted Stock |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  | 156,339 |
Share-based compensation expense | $ |  |  |  |  |  | $ 1,300 | $ 1,700
Total unrecognized compensation expense | $ |  |  |  |  |  | $ 1,800 |
Recognition period |  |  |  |  |  | 1 year 8 months 12 days |
Restricted Stock | Chief Executive Officer |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  | 109,212 |  |
Award vesting period |  |  |  |  | 3 years |  |
Restricted Stock | Chief Financial Officer |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  | 5,000 |  | 20,000 |  |
Restricted Stock | Vice President of Technical Services |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  | 5,000 |  | 20,000 |  |
Restricted Stock | Executive Officers | Forecast |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award vesting period | 3 years | 3 years |  |  |  |  |
Restricted Stock | Directors |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  |  | 5,291 | 5,612 |  |
Award vesting period |  |  |  |  | 1 year |  |
Number of independent directors | independent_director |  |  |  |  | 3 |  |

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