Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2012

Fair Value of Options Granted Calculated Using Weighted Average Assumptions

The fair value of options granted during the three and nine month periods ended September 30, 2012 and 2011 were calculated using the following weighted-average assumptions:

	Three Months Ended					Nine Months Ended
	September 30, 2012		September 30, 2011			September 30, 2012			September 30, 2011
Options granted	—		50,000			46,950			108,550
Weighted average exercise price	$	—	$	48.70		$	41.27		$	48.26
Weighted-average grant date fair value	—		21.33			19.08			21.86
Assumptions:
Expected volatility	—		48.17		%	47.70		%	46.54		%
Expected term (in years)	—		5.0			5.9			5.6
Risk-free interest rate	—		1.90		%	1.43		%	2.30		%
Expected dividend yield	—		—			—			—

Summary of Activity Under Stock Option Plans

A summary of the activity under our stock option plans as of September 30, 2012 and changes during the three and nine month periods then ended, is presented below:

	Options Outstanding		Weighted- Average Exercise Price Per Share		Weighted-Average Remaining Contractual Life in Years	Aggregate Intrinsic Value
Options outstanding at June 30, 2012	2,299,469		$	38.07	4.8	14,513,131
Options granted	—		—
Options exercised	(168,310	)	40.34
Options cancelled	(32,950	)	54.45
Options outstanding at September 30, 2012	2,098,209		38.74		4.6	15,874,392
Options exercisable at September 30, 2012	1,517,217		41.52		3.6	9,055,841
Options vested or expected to vest at September 30, 2012*	2,078,839		38.84		4.6	15,669,835

* In addition to the vested options, we expect a portion of the unvested options to vest at some point in the future.  Options expected to vest are calculated by applying an estimated forfeiture rate to the unvested options.

	Options Outstanding		Weighted- Average Exercise Price Per Share
Options outstanding at December 31, 2011	2,401,809		$	37.54
Options granted	46,950		41.27
Options exercised	(284,801	)	39.99
Options cancelled	(65,749	)	43.31
Options outstanding at September 30, 2012	2,098,209

Performance-Based Restricted Stock

Restricted Stock Activities

	Performance Based Restricted Stock Awards
Non-vested awards outstanding at December 31, 2011	101,730
Awards granted	22,120
Stock issued	(43,750	)
Awards forfeited	(6,642	)
Non-vested awards outstanding at September 30, 2012	73,458

Time Based Restricted Stock

Restricted Stock Activities

	Time-Based Restricted Stock Awards
Non-vested awards outstanding at December 31, 2011	86,707
Awards granted	46,180
Stock issued	(13,020	)
Awards forfeited	(5,395	)
Non-vested awards outstanding at September 30, 2012	114,472

Deferred Stock Units

Restricted Stock Activities

	Deferred Stock Units
Non-vested awards outstanding at December 31, 2011	27,350
Awards granted	17,600
Stock issued	(14,800	)
Non-vested awards outstanding at September 30, 2012	30,150