| **Employee Stock And Incentive Plan (Summary Of Options Outstanding And Options Exercisable) (Details) - Stock Options [Member]** | 12 Months Ended          |
|-----------------------------------------------------------------------------------------------------------------------------------|--------------------------|
||
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                       |                     |
| Options Outstanding, Shares | shares                                                                                              | 427,335                  |
| Options Outstanding, Weighted Average Remaining Life                                                                              | 1 year 10 months 24 days |
| Options Outstanding, Weighted Average Exercise Price                                                                              | $ 15.55                  |
| $13.00 - 14.99 [Member]                                                                                                           |                     |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                       |                     |
| Range of prices, Lower limit                                                                                                      | 13.00                    |
| Range of prices, Upper limit                                                                                                      | $ 14.99                  |
| Options Outstanding, Shares | shares                                                                                              | 121,707                  |
| Options Outstanding, Weighted Average Remaining Life                                                                              | 3 years 1 month 6 days   |
| Options Outstanding, Weighted Average Exercise Price                                                                              | $ 13.72                  |
| $15.00 - 15.99 [Member]                                                                                                           |                     |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                       |                     |
| Range of prices, Lower limit                                                                                                      | 15.00                    |
| Range of prices, Upper limit                                                                                                      | $ 15.99                  |
| Options Outstanding, Shares | shares                                                                                              | 127,779                  |
| Options Outstanding, Weighted Average Remaining Life                                                                              | 2 years 2 months 12 days |
| Options Outstanding, Weighted Average Exercise Price                                                                              | $ 15.30                  |
| $16.00 - 16.99 [Member]                                                                                                           |                     |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                       |                     |
| Range of prices, Lower limit                                                                                                      | 16.00                    |
| Range of prices, Upper limit                                                                                                      | $ 16.99                  |
| Options Outstanding, Shares | shares                                                                                              | 117,025                  |
| Options Outstanding, Weighted Average Remaining Life                                                                              | 1 year 2 months 12 days  |
| Options Outstanding, Weighted Average Exercise Price                                                                              | $ 16.15                  |
| $17.00 - 19.99 [Member]                                                                                                           |                     |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                       |                     |
| Range of prices, Lower limit                                                                                                      | 17.00                    |
| Range of prices, Upper limit                                                                                                      | $ 19.99                  |
| Options Outstanding, Shares | shares                                                                                              | 60,824                   |
| Options Outstanding, Weighted Average Remaining Life                                                                              | 1 month 6 days           |
| Options Outstanding, Weighted Average Exercise Price                                                                              | $ 18.61                  |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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| X                                                                                                                                               |
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