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Stock-Based Compensation And Other Benefit Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 28, 2018 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Stock options, authorized |  |  | 2,404,442 |  |
Stock option granted, reduction ratio for numbers authorized |  |  | 1 |  |
Stock-based compensation |  |  | $ 1,098 | $ 192 | $ 3,810
Tax benefits related to stock based compensation |  |  | $ 0 |  |
Options exercised |  |  | 37,000 |  |
Number of Shares Underlying Options, Granted |  |  | 1,629,000 |  |
Weighted Average Exercise Price Per Share, Granted |  |  | $ 0.99 | $ 1.14 | $ 4.41
Weighted Average Grant Price, Awards granted |  |  | $ 0.49 | $ 0.49 | $ 1.65
Other benefit plans, cost |  |  | $ 200 | $ 300 | $ 400
Cash proceeds from stock options exercised |  |  | $ 39 | $ 0 | 0
Non-Employee Grants [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Number of Shares Underlying Options, Granted |  |  | 465,950 |  |
Stock Option [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards, vesting period |  |  | 5 years |  |
Options exercised |  |  |  | 0 |
Total intrinsic value of options exercised |  |  | $ 0 |  | 300
Number of Shares Underlying Options, Granted |  |  | 1,162,930 |  |
Unrecognized compensation costs |  |  | $ 300 |  |
Compensation costs expected to be recognized |  |  | 1 year 6 months |  |
Stock Option [Member] | Subsequent Event [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Number of Shares Underlying Options, Granted | 494,941 |  |  |  |
Weighted Average Exercise Price Per Share, Granted | $ 0.86 |  |  |  |
Stock Option [Member] | Employee Grants Of 1,162,930 [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards, vesting period |  |  | 3 years |  |
Restricted Stock [Member] |  |  |  |  |
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 7 months 6 days |  |
Vest-date fair value |  |  | $ 300 | $ 600 | $ 700
Awards granted |  |  | 426,000 |  |
Weighted Average Grant Price, Awards granted |  |  | $ 0.98 |  |
Weighted Average Grant Price, Awards granted |  |  | $ 0.98 | $ 1.11 | $ 3.34
Restricted Stock [Member] | Subsequent Event [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards granted | 323,474 |  |  |  |
Weighted Average Grant Price, Awards granted | $ 0.86 |  |  |  |
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 Spread |  |  | 300.00% |  |
Share-Based Compensation Arrangement By Share-Based Payment Award Grant Date Share Price |  |  | $ 1.04 | $ 1.04 |
Stock-based compensation |  |  | $ 100 | $ 25 |
Awards, vesting period |  |  | 3 years |  |
Award granted life |  |  | 5 years |  |
Awards granted |  | 815,355 | 1,049,528 |  |
Weighted Average Grant Price, Awards granted |  |  | $ 1.20 |  |
Stock Appreciation Rights (SARs) [Member] | Subsequent Event [Member] |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Awards granted | 2,373,411 |  |  |  |
Weighted Average Grant Price, Awards granted | $ 0.86 |  |  |  |
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 |  |
Maximum [Member] | 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 Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&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://www.xbrl.org/2003/role/presentationRef -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=96867065&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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. + References No definition available. + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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