Stock-Based Compensation (Schedule Of Range Of Exercise Prices For Outstanding Options) (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Range One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 7.12
Range of Prices, Upper Limit	$ 9.65
Options Outstanding	304,200
Weighted Average Remaining Contractual Life (Years)	44 months 9 days
Range Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 10.26
Range of Prices, Upper Limit	$ 18.05
Options Outstanding	384,466
Weighted Average Remaining Contractual Life (Years)	41 months 23 days
Range Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 22.92
Range of Prices, Upper Limit	$ 30.05
Options Outstanding	211,360
Weighted Average Remaining Contractual Life (Years)	80 months 26 days
Range Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 40.38
Range of Prices, Upper Limit	$ 45.70
Options Outstanding	110,609
Weighted Average Remaining Contractual Life (Years)	97 months 18 days
Range Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 63.98
Range of Prices, Upper Limit	$ 68.18
Options Outstanding	168,767
Weighted Average Remaining Contractual Life (Years)	111 months 8 days

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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

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

-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=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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

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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

+ Details

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