Stock-Based Compensation Expense (Tables)

12 Months Ended

Dec. 31, 2011

Stock-Based Compensation Expense [Abstract]

Schedule Of Fixed-Price Stock Options

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2010		1,972,522		$	24.17	7.2	$	62,357
Granted		401,500			56.34
Exercised		(169,350	)		13.17
Forfeited		(33,500	)		34.37
Outstanding at December 31, 2011		2,171,172		$	30.82	7.1	$	46,846
Exercisable at December 31, 2011		426,937		$	22.54	4.1	$	12,368

Schedule Of Fair Value Of Each Option Granted Estimated With Weighted-Average Assumptions

	Year Ended December 31,
	2011			2010			2009
Dividend yield		1.53	%		1.66	%		2.13	%
Volatility		33.04	%		33.13	%		32.94	%
Average expected life (years)		6			6			6
Risk-free interest rate		3.67	%		3.92	%		3.37	%
Fair value of options granted	$	18.42		$	13.76		$	6.70

Schedule Of Nonvested Performance Unit Awards

	Year Ended December 31,
	2011					2010					2009
	Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value
Nonvested, beginning of period		184,196		$	41.88		7,500		$	38.41		1,263,500		$	30.04
Granted		190,700			56.14		198,700			41.94		—			—
Vested		(2,946	)		38.41		(2,947	)		38.41		(575,890	)		21.60
Forfeited		(1,800	)		48.26		(19,057	)		41.64		(680,110	)		37.10
Nonvested, end of period		370,150			49.23		184,196			41.88		7,500			38.41

Schedule Of Non-Performance Based Restricted Stock Awards

	Year Ended December 31,
	2011					2010					2009
	Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value
Nonvested, beginning of period		333,416		$	34.38		535,625		$	35.10		536,700		$	36.53
Granted		63,600			58.43		92,750			40.98		88,625			21.85
Vested		(159,751	)		35.94		(250,126	)		37.48		(69,700	)		28.98
Forfeited		(9,000	)		48.64		(44,833	)		39.43		(20,000	)		36.03
Nonvested, end of period		228,265			41.35		333,416			34.38		535,625			35.10