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Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock Narrative (Details) - Restricted Stock $ in Millions |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 17, 2021 shares | Apr. 01, 2021 shares | Mar. 18, 2021 independent_director executive_officer shares | Dec. 31, 2021 USD ($) shares | Dec. 31, 2020 USD ($) shares | Dec. 31, 2019 shares | Jun. 20, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares outstanding (in shares) |  |  |  | 276,319 | 258,101 | 279,766 |
Granted (in shares) |  |  |  | 156,339 | 123,185 |  |
Stock based compensation expense | $ |  |  |  | $ 1.7 | $ 2.2 |  |
Total unrecognized compensation expense | $ |  |  |  | $ 1.4 |  |  |
Recognition period |  |  |  | 3 years |  |  |
Chief Financial Officer |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  | 129,212 |  |  |  |
Executive Officer |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award vesting period | 3 years |  | 3 years |  |  |  |
Number of executive officers | executive_officer |  |  | 2 |  |  |  |
Vice President of Technical Services |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) | 5,000 |  |  |  |  |  |
Director |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award vesting period |  |  |  | 1 year |  |  |
Granted (in shares) |  | 5,291 | 5,612 |  |  |  |
Number of independent directors | independent_director |  |  | 3 |  |  |  |
Equity Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares authorized (in shares) |  |  |  |  |  |  | 500,000
Shares outstanding (in shares) |  |  |  | 276,319 |  |  |
Award vesting period |  |  |  | 3 years |  |  |
2009 Restricted Stock/Units Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Issuance under the equity incentive plan (in shares) |  |  |  | 47,135 |  |  |

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