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Stock-Based Compensation (Restricted Stock) (Details) - Restricted Stock - USD ($) $ in Millions |  | 9 Months Ended
--- | --- | ---
Mar. 29, 2019 | Sep. 30, 2019 | Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based compensation expense |  | $ 1.7 | $ 1.6
Total unrecognized compensation expense |  | $ 4.3 |
Unrecognized compensation cost related to awards, vesting period |  | 3 years |
Chief Executive Officer |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Grants in period (in shares) | 131,674 |  |
Award vesting period | 3 years |  |
Chief Financial Officer |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Grants in period (in shares) | 20,000 |  |
Award vesting period | 3 years |  |
Vice President of Technical Services |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Grants in period (in shares) | 20,000 |  |
Award vesting period | 3 years |  |
Directors |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Grants in period (in shares) |  | 23,136 |
Award vesting period |  | 1 year |

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