Stock Option And Stock Award Plans (Summary Of Additional Information On Stock Options Outstanding And Exercisable) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Shares	1,164,120
Options Outstanding, Weighted Average, Remaining Contractual Life (Years)	4 years 2 months 14 days
Options Outstanding, Weighted Average, Exercise Price	$ 19.59
Options Outstanding, Aggregate Intrinsic Value	$ 3,785
Options Exercisable, Shares	800,050
Options Exercisable, Weighted Average Exercise Price	$ 18.17
Options Exercisable, Aggregate Intrinsic Value	3,562
- To 15.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 0
Range of Exercise Prices, Maximum	$ 15
Options Outstanding, Shares	26,000
Options Outstanding, Weighted Average, Remaining Contractual Life (Years)	0 years 10 months 24 days
Options Outstanding, Weighted Average, Exercise Price	$ 14.06
Options Outstanding, Aggregate Intrinsic Value	219
Options Exercisable, Shares	26,000
Options Exercisable, Weighted Average Exercise Price	$ 14.06
Options Exercisable, Aggregate Intrinsic Value	219
15.01 To 17.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 15.01
Range of Exercise Prices, Maximum	$ 17.5
Options Outstanding, Shares	314,500
Options Outstanding, Weighted Average, Remaining Contractual Life (Years)	1 year 2 months 13 days
Options Outstanding, Weighted Average, Exercise Price	$ 16.53
Options Outstanding, Aggregate Intrinsic Value	1,873
Options Exercisable, Shares	314,500
Options Exercisable, Weighted Average Exercise Price	$ 16.53
Options Exercisable, Aggregate Intrinsic Value	1,873
17.51 To 20.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 17.51
Range of Exercise Prices, Maximum	$ 20
Options Outstanding, Shares	488,870
Options Outstanding, Weighted Average, Remaining Contractual Life (Years)	3 years 3 months 19 days
Options Outstanding, Weighted Average, Exercise Price	$ 19.03
Options Outstanding, Aggregate Intrinsic Value	1,693
Options Exercisable, Shares	417,550
Options Exercisable, Weighted Average Exercise Price	$ 18.97
Options Exercisable, Aggregate Intrinsic Value	1,470
20.01 To 25.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 20.01
Range of Exercise Prices, Maximum	$ 25
Options Outstanding, Shares	330,250
Options Outstanding, Weighted Average, Remaining Contractual Life (Years)	8 years 8 months 12 days
Options Outstanding, Weighted Average, Exercise Price	$ 23.61
Options Outstanding, Aggregate Intrinsic Value	0
Options Exercisable, Shares	40,875
Options Exercisable, Weighted Average Exercise Price	$ 24.84
Options Exercisable, Aggregate Intrinsic Value	0
25.01 To 30.01
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 25.01
Range of Exercise Prices, Maximum	$ 30.01
Options Outstanding, Shares	4,500
Options Outstanding, Weighted Average, Remaining Contractual Life (Years)	8 years 7 months 7 days
Options Outstanding, Weighted Average, Exercise Price	$ 30.01
Options Outstanding, Aggregate Intrinsic Value	0
Options Exercisable, Shares	1,125
Options Exercisable, Weighted Average Exercise Price	$ 30.01
Options Exercisable, Aggregate Intrinsic Value	$ 0

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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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

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-Publisher FASB

-Name Accounting Standards Codification

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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

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-Publisher FASB

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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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-Publisher FASB

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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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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://www.xbrl.org/2003/role/presentationRef

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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

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-Publisher FASB

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