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Stock Option And Stock Award Plans (Summary Of Additional Information On Stock Options Outstanding And Exercisable) (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Options Outstanding, Shares | 1,628,903 |
Options Outstanding, Weighted Average, Remaining Contractual Life (Years) | 5 years |
Options Outstanding, Weighted Average, Exercise Price | $ 19.13 |
Options Outstanding, Aggregate Intrinsic Value | $ 5,520,800 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | 360,218 | 275,392
Options Exercisable, Weighted Average Exercise Price | $ 20.81 |
Options Exercisable, Aggregate Intrinsic Value | $ 835,569 |
- To 15.00 |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Range of Exercise Prices, Minimum | $ 0 |
Range of Exercise Prices, Maximum | $ 15 |
Options Outstanding, Shares | 0 |
Options Outstanding, Weighted Average, Remaining Contractual Life (Years) | 0 years |
Options Outstanding, Weighted Average, Exercise Price | $ 0.00 |
Options Outstanding, Aggregate Intrinsic Value | $ 0 |
Options Exercisable, Shares | 0 |
Options Exercisable, Weighted Average Exercise Price | $ 0.00 |
Options Exercisable, Aggregate Intrinsic Value | $ 0 |
15.01 To 17.00 |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Range of Exercise Prices, Minimum | $ 15.01 |
Range of Exercise Prices, Maximum | $ 17.5 |
Options Outstanding, Shares | 163,641 |
Options Outstanding, Weighted Average, Remaining Contractual Life (Years) | 4 years 4 months 21 days |
Options Outstanding, Weighted Average, Exercise Price | $ 15.65 |
Options Outstanding, Aggregate Intrinsic Value | $ 1,096,395 |
Options Exercisable, Shares | 104,326 |
Options Exercisable, Weighted Average Exercise Price | $ 15.65 |
Options Exercisable, Aggregate Intrinsic Value | $ 698,984 |
17.51 To 20.00 |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Range of Exercise Prices, Minimum | $ 17.51 |
Range of Exercise Prices, Maximum | $ 20 |
Options Outstanding, Shares | 1,255,670 |
Options Outstanding, Weighted Average, Remaining Contractual Life (Years) | 5 years 3 months 29 days |
Options Outstanding, Weighted Average, Exercise Price | $ 18.83 |
Options Outstanding, Aggregate Intrinsic Value | $ 4,424,405 |
Options Exercisable, Shares | 46,300 |
Options Exercisable, Weighted Average Exercise Price | $ 19.40 |
Options Exercisable, Aggregate Intrinsic Value | $ 136,585 |
20.01 To 25.00 |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Range of Exercise Prices, Minimum | $ 20.01 |
Range of Exercise Prices, Maximum | $ 25 |
Options Outstanding, Shares | 209,592 |
Options Outstanding, Weighted Average, Remaining Contractual Life (Years) | 3 years 6 months 7 days |
Options Outstanding, Weighted Average, Exercise Price | $ 23.69 |
Options Outstanding, Aggregate Intrinsic Value | $ 0 |
Options Exercisable, Shares | 209,592 |
Options Exercisable, Weighted Average Exercise Price | $ 23.69 |
Options Exercisable, Aggregate Intrinsic Value | $ 0 |

X
- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. + 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 (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + 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 (e)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + 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 (e) -URI http://asc.fasb.org/extlink&oid=116856206&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 floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + 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 (c)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + 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 (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + 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 (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + 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 (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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