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Stock-Based Compensation and Other Benefit Plans (Narrative) (Details) $ / shares in Units, $ in Thousands |  |  |  |  |  | 12 Months Ended
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Jun. 06, 2019 $ / shares shares | May 10, 2019 $ / shares shares | Apr. 01, 2019 $ / shares shares | Feb. 28, 2019 $ / shares shares | Feb. 28, 2018 $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares | Dec. 31, 2018 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Stock options, authorized | shares |  |  |  |  |  | 68,241 |  |
Stock-based compensation | $ |  |  |  |  |  | $ 3,506 | $ 2,388 | $ 1,098
Payments to settle stock appreciation rights | $ |  |  |  |  |  | 491 | 82 |
Cash proceeds from stock options exercised | $ |  |  |  |  |  | $ 300 | $ 500 | $ 39
Options granted | shares |  |  |  |  |  | 923,000 |  |
Options granted, weighted average exercise price |  |  |  |  |  | $ 2.08 | $ 1.05 | $ 0.99
Stock option granted, reduction ratio for numbers authorized |  |  |  |  |  | 1 |  |
Other benefit plans, cost | $ |  |  |  |  |  | $ 400 | $ 300 | $ 200
Weighted average grant date fair value - ($/share) |  |  |  |  |  | $ 1.06 | $ 0.68 | $ 0.49
Employees [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Awards, vesting period |  |  |  | 3 years |  |  | 3 years | 3 years
Options granted | shares | 257,228 |  | 44,163 | 622,140 |  |  | 494,941 | 1,162,930
Options granted, weighted average exercise price | $ 1.43 |  | $ 2.29 | $ 2.33 |  |  | $ 0.86 |
Non-Employee Directors [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Options granted | shares |  |  |  |  |  |  | 175,644 | 465,950
Options granted, weighted average exercise price |  |  |  |  |  |  | $ 1.60 |
Stock Option [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Awards, vesting period |  |  |  |  |  | 5 years |  |
Total intrinsic value of options exercised | $ |  |  |  |  |  | $ 300 | $ 600 | $ 0
Unrecognized compensation costs | $ |  |  |  |  |  | $ 300 |  |
Compensation costs expected to be recognized |  |  |  |  |  | 1 year 6 months |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Awards, vesting period |  |  |  |  |  | 3 years |  |
Other awards granted | shares | 111,888 |  | 22,926 | 174,464 | 323,474 | 309,000 |  |
Other awards granted, weighted average exercise price | $ 1.43 |  | $ 2.29 | $ 2.33 | $ 0.86 | $ 2.00 |  |
Unrecognized compensation costs | $ |  |  |  |  |  | $ 200 |  |
Compensation costs expected to be recognized |  |  |  |  |  | 1 year 6 months |  |
Vest-date fair value | $ |  |  |  |  |  | $ 600 | $ 400 | $ 300
Weighted average grant date fair value - ($/share) |  |  |  |  |  | $ 2.00 | $ 1.71 | $ 0.98
Stock Appreciation Rights (SARs) [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation | $ |  |  |  |  |  | $ 2,500 |  |
Award granted life |  | 5 years |  | 5 years |  |  | 5 years |
Awards, vesting period |  | 3 years |  | 3 years |  |  | 3 years | 3 years
Other awards granted | shares |  | 196,892 |  | 951,699 | 2,373,411 | 1,148,000 | 1,049,528 |
Other awards granted, weighted average exercise price |  | $ 1.72 |  | $ 2.33 | $ 0.86 |  | $ 1.20 |
Share-Based Compensation Arrangement By Share-Based Payment Award Life |  |  |  |  |  | 5 years |  |
Stock Appreciation Rights (SARs) [Member] | First Vesting Milestone [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based compensation, vesting hurdle share price |  |  |  |  |  |  | 1.30 |
Stock Appreciation Rights (SARs) [Member] | Second Vesting Milestone [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based compensation, vesting hurdle share price |  |  |  |  |  |  | 1.50 |
Stock Appreciation Rights (SARs) [Member] | Third Vesting Milestone [Member] |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based compensation, vesting hurdle share price |  |  |  |  |  |  | $ 1.75 |

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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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