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Stock Option And Stock Award Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 1,628,903 | 890,116 | 608,520 | 500,919
Options may be granted to purchase specified number of common shares under stock option plan, maximum term | 10 years |  |  |
The total intrinsic value of stock options exercised | $ 0.1 | $ 0.4 | $ 0.2 |
The grant-date fair value of stock option-based awards vested | 0.5 | $ 0.1 | $ 0.4 |
Restricted Stock or Unit Expense | $ 1.3 |  |  |
Stock options exercisable | 360,218 | 275,392 |  |
Total stock options available for grant | 954,454 |  |  |
Restricted Stock [Member] |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Option vesting period | 3 years |  |  |
Stock Option Based Awards [Member] |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Unrecognized compensation cost | $ 1.9 |  |  |
Weighted average period for the cost expected to be recognized | 397 days |  |  |
Non-Vested Restricted Stock And Other Stock-Based Awards |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Unrecognized compensation cost | $ 2.5 |  |  |
Weighted average period for the cost expected to be recognized | 525 days |  |  |
Share-based Payment Arrangement, Tranche Two [Member] |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period | 5 years |  |  |
Share-based Payment Arrangement, Tranche One [Member] |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period | 7 years |  |  |
Share-based Payment Arrangement, Tranche Two [Member] | Stock Option Based Awards [Member] |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Option vesting period | 2 years |  |  |
Share-based Payment Arrangement, Tranche One [Member] | Stock Option Based Awards [Member] |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |
Option vesting period | 3 years |  |  |

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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + 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=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents 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=116856206&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=116856206&loc=d3e5070-113901 + Details
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