Stock-Based Compensation

9 Months Ended

Sep. 30, 2012

Stock-Based Compensation [Abstract]

Stock-Based Compensation

(9) Stock-Based Compensation

The Company's stock-based compensation (benefit) expense for the three and nine months ended September 30, 2012 included performance-based restricted stock units ("PRSUs"), non-qualified stock options, restricted stock units (RSUs) and deferred stock units (DSUs). A summary of the Company's stock-based compensation (benefit) expense is presented below:

	Three Months Ended							Nine Months Ended
	September 30,							September 30,
	2012				2011			2012				2011
PRSU (benefit) expense		$	(5,207	)		$	1,708		$	(1,126	)		$	5,719
Option expense			911				1,237			3,169				3,931
RSU/DSU expense			547				471			1,618				1,485
Total stock-based compensation (benefit) expense		$	(3,749	)		$	3,416		$	3,661			$	11,135

A summary of the Company's PRSU activity and related information for the nine months ended September 30, 2012 is presented below:  

	Number of Shares	Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value
Awards outstanding at December 31, 2011	285	$	37.93
Granted	134		71.52
Vested	—		—
Forfeited	—		—
Awards outstanding at September 30, 2012	419	$	48.69	$	9,793

The maximum number of shares to be awarded under the PRSUs granted during the nine months ended September 30, 2012 and 2011 will be 403 and 443 shares, and will vest, if earned, at the end of the three-year performance periods ending on December 31, 2014 and 2013, respectively. The Company recorded a benefit in the Condensed Consolidated Statement of Operations of $7,974 and $9,536, respectively, for three and nine months ended September 30, 2012, related to the PRSUs granted during the nine months ended September 30, 2012 and 2011, after re-evaluation of the probability of meeting certain required financial metrics.

A summary of the Company's stock option activity and related information for the nine months ended September 30, 2012 is presented below:

	Number of Shares	Weighted-Average Grant Date Fair Value		Weighted-Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Options outstanding December  31, 2011	3,408	$	11.15
Granted	98		70.24
Forfeited	—		—
Exercised	840		12.56
Options outstanding at September 30, 2012	2,666	$	15.98	5.91	$	18,975
Options exercisable at September 30, 2012	2,090	$	13.88	5.55	$	19,868

The aggregate intrinsic value of options exercised during the three months ended September 30, 2012 and 2011 was $770 and $10,961 respectively.  The aggregate intrinsic value of options exercised during the nine months ended September 30, 2012 and 2011 was $32,206 and $70,276, respectively.

The Company granted 10 DSUs during the nine months ended September 30, 2012. No RSUs were granted during the nine months ended September 30, 2012.

A summary of total unrecognized stock-based compensation expense based on current performance estimates related to the options and DSUs granted during the nine months ended September 30, 2012 is presented below:

	September 30, 2012		Weighted Average Remaining Vesting Period (Years)
Unrecognized stock option expense		2,526		2.26
Unrecognized DSU expense		360		0.58
Total unrecognized stock-based compensation expense	$	2,886		2.05