Stock-Based Compensation Plans (Schedule Of Other Data For Stock Options, Stock Awards And PSUs) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation at the end of the year	$ 34,640
Weighted average period over which unrecognized compensation to be recognized (years)	2 years 3 months 18 days
Actual income tax benefit realized	$ 25,193
Aggregate intrinsic value vested and expected to vest	225,226
Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual income tax benefit realized	181
Perfromance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation at the end of the year	$ 7,475
Weighted average period over which unrecognized compensation to be recognized (years)	1 year 8 months 12 days
Actual income tax benefit realized	$ 2,489
Aggregate intrinsic value vested and expected to vest	$ 36,306

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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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.

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