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Stock-Based Compensation And Other Benefit Plans (Narrative) (Details) $ / shares in Units, $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Feb. 28, 2019 $ / shares shares | Feb. 28, 2018 $ / shares shares | Dec. 31, 2018 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Stock options, authorized | shares |  |  | 1,112,527 |  |
Stock option granted, reduction ratio for numbers authorized |  |  | 1 |  |
Stock-based compensation | $ |  |  | $ 2,306 | $ 1,098 | $ 192
Tax benefits related to stock based compensation | $ |  |  | $ 0 |  |
Number of Shares Underlying Options, Granted | shares |  |  | 671,000 |  |
Weighted Average Exercise Price Per Share, Granted |  |  | $ 1.05 | $ 0.99 | $ 1.14
Weighted Average Grant Price, Awards granted |  |  | $ 0.68 | $ 0.49 | $ 0.49
Other benefit plans, cost | $ |  |  | $ 300 | $ 200 | $ 300
Options exercised | shares |  |  | 528,000 |  | 0
Cash proceeds from stock options exercised | $ |  |  | $ 500 | 39,000 | $ 0
Non-Employee Grants [Member] | Non-Employee Director [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Options granted, exercise price |  |  | $ 1.60 |  |
Number of Shares Underlying Options, Granted | shares |  |  | 175,644 |  |
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 | $ |  |  | $ 600 | 0 |
Number of Shares Underlying Options, Granted | shares |  | 622,140 | 494,941 |  |
Weighted Average Exercise Price Per Share, Granted |  | $ 2.33 |  |  |
Unrecognized compensation costs | $ |  |  | $ 200 |  |
Compensation costs expected to be recognized |  |  | 1 year 1 month 6 days |  |
Stock Option [Member] | Employees [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards, vesting period |  |  | 3 years |  |
Options granted, exercise price |  |  | $ 0.86 |  |
Restricted Stock |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards, vesting period |  |  | 3 years |  |
Unrecognized compensation costs | $ |  |  | $ 200 |  |
Compensation costs expected to be recognized |  |  | 1 year 2 months 12 days |  |
Vest-date fair value | $ |  |  | $ 400 | $ 300 | $ 600
Awards granted | shares |  | 174,464 | 398,000 |  |
Weighted Average Grant Price, Awards granted |  | $ 2.33 | $ 1.00 |  |
Weighted Average Grant Price, Awards granted |  |  | $ 1.71 | $ 0.98 | $ 1.11
Stock Appreciation Rights (SARs) [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Share-Based Compensation Arrangement By Share-Based Payment Award Life |  |  | 5 years |  |
Share-Based Compensation Arrangement By Share-Based Payment Award Grant Date Share Price |  |  |  |  | $ 1.04
Stock-based compensation | $ |  |  | $ 1,600 |  |
Awards, vesting period |  |  | 3 years |  |
Award granted life |  |  | 5 years |  |
Awards granted | shares |  | 2,373,411 | 2,373,000 | 1,049,528 | 815,355
Weighted Average Grant Price, Awards granted |  | $ 0.86 |  | $ 1.20 |
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 |
Stock Appreciation Rights (SARs) [Member] | Subsequent Event |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards, vesting period | 3 years |  |  |  |
Award granted life | 5 years |  |  |  |
Awards granted | shares | 951,699 |  |  |  |
Weighted Average Grant Price, Awards granted | $ 2.33 |  |  |  |
Maximum | Stock Appreciation Rights (SARs) [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Share-Based Compensation Arrangement By Share-Based Payment Award Spread |  |  |  |  | 300.00%

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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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=109197908&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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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=109197908&loc=d3e5070-113901 + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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