Stockholders Equity and Stock Options (Tables)

12 Months Ended

Dec. 31, 2011

Schedule Of Weighted-Average Assumptions Used In Calculation Of Fair Value

The following table summarizes weighted-average assumptions used in our calculations of fair value for the years ended December 31, 2011, 2010 and 2009:



	Year Ended December 31,
	2011		2010		2009
Volatility	35.08	%	39.02	%	40.13	%
Expected life of options (in years)	2.98		2.95		2.92
Risk-free interest rate	0.81	%	1.25	%	1.48	%
Dividend yield	0.70	%	—	%	—	%

Summary Of Stock Option Activity And Options Outstanding

The following table includes information with respect to stock option activity and stock options outstanding for the years ended December 31, 2011, 2010 and 2009, was as follows:



	Number of Shares		Weighted Average Exercise Price		Aggregate Intrinsic Value
	Number of Shares		Weighted Average Exercise Price		(in thousands)
Shares under option, December 31, 2008	1,961,149		$	35.75
Options granted	1,359,500		$	47.65
Options exercised	(394,949	)	$	31.81	$	6,529
Options cancelled and expired	(207,517	)	$	42.34
Shares under option, December 31, 2009	2,718,183		$	41.85	$	17,643
Options granted	944,500		$	46.50
Options exercised	(391,176	)	$	35.30	$	4,224
Options cancelled and expired	(798,250	)	$	49.42
Shares under option, December 31, 2010	2,473,257		$	42.22	$	7,731
Options granted	986,000		$	38.56
Options exercised	(271,165	)	$	27.94	$	3,087
Options cancelled and expired	(301,982	)	$	45.07
Shares under option, December 31, 2011	2,886,110		$	41.14	$	1,096

Summary Of Non-Vested Stock Options

The following table summarizes non-vested stock options for the year ended December 31, 2011:



	Number of Shares		Weighted Average Fair Value
Non-vested stock options at December 31, 2010	1,459,008		$	12.77
Options granted	986,000		$	9.14
Vested during period	(609,419	)	$	12.75
Options cancelled	(216,334	)	$	12.32
Non-vested shares under option, December 31, 2011	1,619,255		$	10.47

Stock Options Exercisable And Expected To Vest

The following table includes information concerning stock options exercisable and stock options expected to vest at December 31, 2011:



	Options Exercisable	Weighted Average Remaining Contractual Life (years)	Weighted Average Exercise Price		Aggregate Intrinsic Value
	Options Exercisable	Weighted Average Remaining Contractual Life (years)	Weighted Average Exercise Price		(in thousands)
Stock options exercisable	1,266,855	2.1	$	41.49	$	1,096
Stock options expected to vest	1,444,696	3.8	$	41.78	$	—
Options exercisable and expected to vest	2,711,551

Summary Of Restricted Stock Activity

The following table summarizes the restricted stock activity during the years ended December 31, 2010 and 2011:



	Number of Shares		Grant Date Fair Value
	Number of Shares		(in thousands)
Non-vested, December 31, 2009	—
Granted	51,000		$	2,447
Vested	—
Forfeited	(25,000	)	$	1,196
Non-vested, December 31, 2010	26,000
Granted	24,000		$	1,070
Vested	(19,333	)	$	862
Forfeited	—
Non-vested, December 31, 2011	30,667