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Share-Based Compensation (Narrative) (Details) $ / shares in Units, $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($) $ / shares | Dec. 31, 2015 USD ($) $ / shares | May 07, 2015 shares | May 31, 2012 shares | May 31, 2005 shares
Nonemployee director annual stock grants | shares | 20,000 |  |  |  |  |
Share-based compensation expense | $ | $ 2,612 | $ 1,732 | $ 2,134 |  |  |
Weighted Average Fair Value Per Share, Options granted | $ / shares | $ 5.76 | $ 3.65 | $ 4.74 |  |  |
Weighted Average Remaining Contractual Life (Years), Options outstanding | 3 years 4 months 22 days |  |  |  |  |
Number of Shares Authorized, Available to Issue and Outstanding | shares | 1,810,850 |  |  |  |  |
Unrecognized compensation cost | $ | $ 617 |  |  |  |  |
Aggregate Intrinsic Value, Options exercised | $ | $ 2,314 | $ 4,730 | $ 5,551 |  |  |
Aggregate Intrinsic Value, Per Share, Options exercised | $ / shares | $ 13.55 | $ 7.06 | $ 12.69 |  |  |
2012 Plan [Member] |  |  |  |  |  |
Shares available for grants | shares | 951,668 |  |  | 3,000,000 | 1,500,000 |
Stock Option Plan, Award Vesting Period | 5 years |  |  |  |  |
Common stock on date granted term period, years | 10 |  |  |  |  |
Weighted Average Fair Value Per Share, Options granted | $ / shares | $ 5.76 |  |  |  |  |
2005 Plan [Member] |  |  |  |  |  |
Shares available for grants | shares | 0 |  |  |  |  | 1,500,000
Stock Option Plan, Award Vesting Period | 10 years |  |  |  |  |
Common stock on date granted term period, years | 10 |  |  |  |  |
Expected To Be Recognized During 2016 [Member] |  |  |  |  |  |
Unrecognized compensation cost | $ | $ 552 |  |  |  |  |
Expected To Be Recognized During 2017 [Member] |  |  |  |  |  |
Unrecognized compensation cost | $ | $ 65 |  |  |  |  |
Prior To Shareholder Approval of Increase [Member] |  |  |  |  |  |
Nonemployee director annual stock grants | shares | 15,000 |  |  |  |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: 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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + 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)(3) -URI http://asc.fasb.org/extlink&oid=96867065&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://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 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 remaining contractual term for option awards outstanding, 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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