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Stock And Stock Options (Schedule Of Stock Options Outstanding And Exercisable) (Details) - $ / shares | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 3.73 | $ 4.70 | $ 6.10 | $ 5.70
Options Outstanding | 30,000 | 37,500 | 45,625 | 90,025
Options Exercisable | 30,000 |  |  |
$6.20 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 6.20 |  |  |
Options Outstanding | 1,875 |  |  |
Weighted Average Remaining Contractual Life | 3 months 18 days |  |  |
Options Exercisable | 1,875 |  |  |
$4.80 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 4.80 |  |  |
Options Outstanding | 1,875 |  |  |
Weighted Average Remaining Contractual Life | 6 months |  |  |
Options Exercisable | 1,875 |  |  |
$4.10 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 4.10 |  |  |
Options Outstanding | 1,875 |  |  |
Weighted Average Remaining Contractual Life | 9 months 18 days |  |  |
Options Exercisable | 1,875 |  |  |
$4.10 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 4.10 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 1 year |  |  |
Options Exercisable | 2,500 |  |  |
$4.80 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 4.80 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 1 year 2 months 12 days |  |  |
Options Exercisable | 2,500 |  |  |
$4.40 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 4.40 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 1 year 6 months |  |  |
Options Exercisable | 2,500 |  |  |
$4.40 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 4.40 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 1 year 9 months 18 days |  |  |
Options Exercisable | 2,500 |  |  |
$2.50 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 2.50 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 2 years |  |  |
Options Exercisable | 2,500 |  |  |
$2.30 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 2.30 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 2 years 2 months 12 days |  |  |
Options Exercisable | 2,500 |  |  |
$2.70 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 2.70 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 2 years 6 months |  |  |
Options Exercisable | 2,500 |  |  |
$2.20 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 2.20 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 2 years 9 months 18 days |  |  |
Options Exercisable | 2,500 |  |  |
$1.20 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted Average Exercise Price | $ 1.20 |  |  |
Options Outstanding | 2,500 |  |  |
Weighted Average Remaining Contractual Life | 3 years |  |  |
Options Exercisable | 2,500 |  |  |

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- Definition Number of options outstanding, including both vested and non-vested options. + 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=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option 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)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&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=6415400&loc=d3e5070-113901 + Details
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