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Share-Based Compensation (Narrative) (Details) | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Feb. 28, 2019 shares | Feb. 28, 2018 executive shares | Dec. 31, 2020 USD ($) shares | Dec. 31, 2019 USD ($) shares | Dec. 31, 2018 USD ($) shares | Dec. 31, 2017 shares | Feb. 28, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of options outstanding (in shares) |  |  | 67,500 | 67,500 |  |  |
Vesting term |  |  | 4 years |  |  |  |
Options forfeited | 10,000 |  | 0 |  |  |  |
Intrinsic value of stock options exercised | $ |  |  |  | $ 217,064 | $ 42,000 |  |
Total fair value of stock options vested | $ |  |  | $ 141,584 | $ 141,584 | $ 0 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Period |  |  | 3 years |  |  |  |
Restricted Stock And Restricted Stock Unit [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
RSU available for issuance (in share) |  |  | 0 | 0 | 75,250 | 169,000 |
Granted, shares (in shares) |  |  | 0 | 0 | 0 |  |
2015 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares authorized (in shares) |  |  |  |  |  |  | 4,900,000
Options granted during period |  |  | 0 | 0 |  |  |
Compensation expense not yet recognized | $ |  |  | $ 200,000 |  |  |  |
Compensation expense not yet recognized, period for recognition |  |  | 1 year 1 month 6 days |  |  |  |
2015 Plan [Member] | Employee Stock Option [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of options available for issuance (in shares) |  | 80,000 |  |  |  |  |
Number of executives | executive |  | 4 |  |  |  |  |
2005 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Percentage of stock option exercisable per year |  |  | 25.00% |  |  |  |
Stock option expiration period (in years) |  |  | 10 years |  |  |  |
Common Stock [Member] | 2015 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of options outstanding (in shares) |  |  | 70,000 |  |  |  |
Number of shares available for issuance (in shares) |  |  | 4,830,000 |  |  |  |

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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=120381028&loc=d3e5070-113901 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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)(1) -URI http://asc.fasb.org/extlink&oid=120381028&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=120381028&loc=d3e5070-113901 + Details
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