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Stock-Based Compensation (Restricted Stock Narrative) (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Nov. 15, 2019 | Mar. 23, 2017 | Feb. 14, 2017 | Jun. 18, 2014 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Jun. 20, 2019 | Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares outstanding (in shares) |  |  |  |  | 279,766 | 214,630 | 184,389 |  | 139,451
Granted (in shares) |  |  |  |  | 199,810 | 140,988 | 126,432 |  |
Granted (in dollars per share) |  |  |  |  | $ 17.16 | $ 24.55 | $ 27.06 |  |
Share-based compensation expense |  |  |  |  | $ 2,500 | $ 2,200 | $ 3,700 |  |
Total unrecognized compensation expense |  |  |  |  | $ 3,300 |  |  |  |
Unrecognized compensation cost related to stock options, weighted average period for recognition |  |  |  |  | 3 years 3 months |  |  |  |
Chief Executive Officer |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  | 131,674 |  |  |  |  |  |
Award vesting period |  |  | 3 years |  |  |  |  |  |
Chief Financial Officer |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Granted (in shares) |  | 20,000 |  |  |  |  |  |  |
Granted (in dollars per share) | $ 11.18 |  |  |  |  |  |  |  |
Share-based compensation expense | $ 189 |  |  |  |  |  |  |  |
Chief Financial Officer | Minimum |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Granted (in dollars per share) | $ 17.29 |  |  |  |  |  |  |  |
Chief Financial Officer | Maximum |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Granted (in dollars per share) | $ 24.55 |  |  |  |  |  |  |  |
Vice President of Technical Services |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Granted (in shares) |  | 20,000 |  |  |  |  |  |  |
Executive Officer |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Award vesting period |  | 3 years |  |  |  |  |  |  |
Director |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  | 23,136 |  |  |  |
Award vesting period |  |  |  |  | 1 year |  |  |  |
2009 Restricted Stock/Units Plan |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Additional shares authorized (in shares) |  |  |  | 500,000 |  |  |  |  |
Number of shares authorized (in shares) |  |  |  | 800,000 |  |  |  |  |
Shares outstanding (in shares) |  |  |  |  | 123,092 |  |  |  |
Award vesting period |  |  |  |  | 2 years |  |  |  |
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested (in shares) |  |  |  |  | 328,173 |  |  |  |
Equity Incentive Plan |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Number of shares authorized (in shares) |  |  |  |  |  |  |  | 500,000 |

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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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