Stock-Based Compensation (Schedule Of Stock Option Plans Activity) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2012 Year
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding at beginning of year, Shares	1,156
Granted, Shares	754
Exercised, Shares	(203)
Canceled, Shares
Outstanding at June 30, 2012, Shares	1,707
Options exercisable at June 30, 2012, Shares	151
Outstanding at beginning of year, Weighted - Average Exercise Price	$ 38.26
Granted, Weighted - Average Exercise Price	$ 35.76
Exercised, Weighted - Average Exercise Price	$ 30.27
Canceled, Weighted - Average Exercise Price
Outstanding at June 30, 2012,Weighted - Average Exercise Price	$ 38.11
Options exercisable at June 30, 2012, Weighted - Average Exercise Price	$ 28.86
Outstanding at June 30, 2012, Weighted - Average Remaining Contractual Life, years
Options exercisable at June 30, 2012, Weighted - Average Remaining Contractual Life, years
Exercised, Instrinsic Value	$ 2,745
Outstanding at June 30, 2012,Aggregate Intrinsic Value	2,980
Options exercisable at June 30, 2012,Aggregate Intrinsic Value	$ 1,365