Stock Options And Awards (Schedule Of Option Activity) (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Schedule Of Stock Options [Line Items]
Outstanding at December 31, 2011, Number of Options	1,085,906
Granted, Number of Options
Exercised, Number of Options	(280,969)
Forfeited, Number of Options	(53,250)
Outstanding at December 31, 2012, Number of Options	751,687
Exercisable at December 31, 2012, Number of Options	498,878
Outstanding at December 31, 2011, Weighted Average Price	$ 49.50
Granted, Weighted Average Price
Exercised, Weighted Average Price	$ 38.47
Forfeited, Weighted Average Price	$ 61.90
Outstanding at December 31, 2012, Weighted Average Price	$ 52.74
Exercisable at December 31, 2012, Weighted Average Price	$ 46.46
Outstanding at December 31, 2012, Aggregate intrinsic value	$ 15.3
Exercisable at December 31, 2012, Aggregate intrinsic value	$ 13.3
Outstanding at December 31, 2012, Weighted Average Remaining Contractual Life (in years)	6 years 8 months 19 days
Exercisable at December 31, 2012, Weighted Average Remaining Contractual Life (in years)	5 years 11 months 16 days

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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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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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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.

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

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Number of share options (or share units) exercised during the current period.

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