Stock-Based Compensation (Summary Of Stock Option Activity) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock options, Outstanding at December 31, Number of options	3,313,000	3,650,000	4,743,000
Stock options, Granted, Number of options	835,000	571,000	613,000
Stock options, Exercised, Number of options	(402,000)	(833,000)	(1,608,000)
Stock options, Forfeited or expired, Number of options	(124,000)	(75,000)	(98,000)
Stock options, Outstanding at December 31, Number of options	3,622,000	3,313,000	3,650,000
Stock options, Outstanding at December 31, Weighted average exercise price	$ 35.70	$ 29.84	$ 21.24
Stock options, Granted, Weighted average exercise price	$ 32.31	$ 38.95	$ 34.34
Stock options, Exercised, Weighted average exercise price	$ 30.60	$ 12.12	$ 5.71
Stock options, Forfeited or expired, Weighted average exercise price	$ 37.80	$ 37.31	$ 37.76
Stock options, Outstanding at December 31, Weighted average exercise price	$ 35.41	$ 35.70	$ 29.84
Stock Options [Member]
Stock options, Outstanding at December 31, Number of options	3,622,000
Stock options, Outstanding at December 31, Weighted average exercise price	$ 35.41
Options Outstanding - Weighted Average Remaining Contractual Life (Years)	4 years 4 months 24 days
Stock options, Exercisable at December 31, 2014	2,277,000
Stock options, Exercisable at December 31, 2014, Weighted average exercise price	$ 36.13
Options Exercisable - Weighted Average Remaining Contractual Life (Years)	3 years 3 months 18 days
Range of Exercise Prices $27.09-$29.69 [Member] \| Stock Options [Member]
Stock options, Outstanding at December 31, Number of options	21,000
Stock options, Outstanding at December 31, Weighted average exercise price	$ 28.42
Options Outstanding - Weighted Average Remaining Contractual Life (Years)	2 years 10 months 24 days
Stock options, Exercisable at December 31, 2014	17,000
Stock options, Exercisable at December 31, 2014, Weighted average exercise price	$ 28.53
Options Exercisable - Weighted Average Remaining Contractual Life (Years)	2 years 6 months
Range of Exercise Prices $30.23-$35.91 [Member] \| Stock Options [Member]
Stock options, Outstanding at December 31, Number of options	1,744,000
Stock options, Outstanding at December 31, Weighted average exercise price	$ 32.04
Options Outstanding - Weighted Average Remaining Contractual Life (Years)	4 years 10 months 24 days
Stock options, Exercisable at December 31, 2014	819,000
Stock options, Exercisable at December 31, 2014, Weighted average exercise price	$ 32.83
Options Exercisable - Weighted Average Remaining Contractual Life (Years)	3 years 1 month 6 days
Range of Exercise Prices $36.22-$39.91 [Member] \| Stock Options [Member]
Stock options, Outstanding at December 31, Number of options	1,443,000
Stock options, Outstanding at December 31, Weighted average exercise price	$ 37.52
Options Outstanding - Weighted Average Remaining Contractual Life (Years)	4 years 3 months 18 days
Stock options, Exercisable at December 31, 2014	1,117,000
Stock options, Exercisable at December 31, 2014, Weighted average exercise price	$ 37.10
Options Exercisable - Weighted Average Remaining Contractual Life (Years)	3 years 10 months 24 days
Range of Exercise Prices $40.15-$51.47 [Member] \| Stock Options [Member]
Stock options, Outstanding at December 31, Number of options	414,000
Stock options, Outstanding at December 31, Weighted average exercise price	$ 42.64
Options Outstanding - Weighted Average Remaining Contractual Life (Years)	2 years 10 months 24 days
Stock options, Exercisable at December 31, 2014	324,000
Stock options, Exercisable at December 31, 2014, Weighted average exercise price	$ 41.56
Options Exercisable - Weighted Average Remaining Contractual Life (Years)	1 year 10 months 24 days

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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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