Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2012

Earnings Per Common Share

Components of basic and diluted earnings per share

	Three Months Ended September 30,				Nine Months Ended September 30,
	2012		2011		2012		2011
Numerator:
Income from continuing operations	$	78,111	$	80,615	$	221,187	$	174,054
Income from discontinued operations	—		3,783		—		625
Net income	$	78,111	$	84,398	$	221,187	$	174,679
Denominator:
Weighted average outstanding shares — basic	51,514		58,321		52,626		58,087
Effect of dilutive securities (1):
Convertible notes	662		1,489		136		2,444
Warrants	—		—		—		—
Stock options	1,414		1,400		1,087		1,531
Weighted average shares — diluted	53,590		61,210		53,849		62,062
Earnings per common share:
Basic
Continuing operations	$	1.52	$	1.38	$	4.20	$	3.00
Discontinued operations	0.00		0.07		0.00		0.01
Net income per basic common share	$	1.52	$	1.45	$	4.20	$	3.01
Diluted
Continuing operations	$	1.46	$	1.32	$	4.11	$	2.80
Discontinued operations	0.00		0.06		0.00		0.01
Net income per diluted common share	$	1.46	$	1.38	$	4.11	$	2.81
Stock options and warrants excluded from calculation (2)	11,026		7,922		11,761		6,446

(1)Calculated using the treasury stock method.

(2)Certain stock options and warrants were excluded from the computation of diluted earnings per share because their impact would be anti-dilutive.

Stock Options

Stock Option Plan

Schedule of stock option activity

	Number of Options		Weighted- Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding at January 1, 2012	4,923,377		$	36.98
Granted	—		—
Exercised	(373,457	)	25.31
Forfeited	(3,858	)	6.95
Outstanding and exercisable at September 30, 2012	4,546,062		$	37.96	5.2	$	85,436

Share-based compensation expense (benefit) related to employee stock options

	Three Months Ended September 30,						Nine Months Ended September 30,
	2012			2011			2012			2011
Research and development	$	—		$	3		$	—		$	196
Selling, general and administrative	4,042			5			6,371			315
Share-based compensation expense before taxes	4,042			8			6,371			511
Related income tax benefit	(1,480		)	(3		)	(2,333		)	(189		)
Share-based compensation expense net of taxes	$	2,562		$	5		$	4,038		$	322
Share-based compensation capitalized as part of inventory	$	—		$	—		$	—		$	15

Summary of employee and non-employee stock option exercise data

	Three Months Ended September 30,				Nine Months Ended September 30,
	2012		2011		2012		2011
Number of options exercised	246,401		20,135		386,515		820,572
Cash received	$	6,575	$	224	$	9,689	$	23,948

Employee Stock Purchase Plan (ESPP)

Stock Option Plan

Summary of assumptions to estimate the fair value of shares to be purchased

	Initial Offering Period beginning September 5, 2012
Expected volatility	29.0	%
Risk-free interest rate	0.1	%
Expected term (in years)	0.5
Expected dividend yield	0.0	%
Expected forfeiture rate	4.6	%