Stock-based Compensation Expense

3 Months Ended

Mar. 31, 2012

Stock-based Compensation Expense

Stock-based Compensation Expense

K. Stock-based Compensation Expense

        The Company issues stock options, restricted stock and restricted stock units with service conditions, which are generally the vesting periods of the awards. The Company also has issued, to certain members of senior management, restricted stock and restricted stock units that vest upon the earlier of the satisfaction of (i) a performance condition or (ii) a service condition, and stock options that vest upon the earlier of the satisfaction of (a) performance conditions or (b) a service condition. In addition, the Company issues shares pursuant to an employee stock purchase plan ("ESPP").

        The effect of stock-based compensation expense during the three months ended March 31, 2012 and 2011 was as follows:

	Three Months Ended March 31,
	2012			2011
	(in thousands)
Stock-based compensation expense by type of award:
Stock options	$	18,222		$	19,624
Restricted stock and restricted stock units		7,286			6,830
ESPP share issuances		2,430			1,579
Less stock-based compensation expense capitalized to inventories		(250	)		(154	)
Total stock-based compensation expense included in costs and expenses	$	27,688		$	27,879
Stock-based compensation expense by line item:
Research and development expenses	$	17,204		$	18,549
Sales, general and administrative expenses		10,484			9,330
Total stock-based compensation expense included in costs and expenses	$	27,688		$	27,879

        During the three months ended March 31, 2012 and 2011, the Company capitalized $0.3 million and $0.2 million, respectively, of stock-based compensation expense to inventories, all of which was attributable to employees who supported the Company's manufacturing operations related to the Company's products.

        The following table sets forth the Company's unrecognized stock-based compensation expense, net of estimated forfeitures, as of March 31, 2012 by type of award and the weighted-average period over which that expense is expected to be recognized:

	As of March 31, 2012
	Unrecognized Expense Net of Estimated Forfeitures		Weighted-average Recognition Period
	(in thousands)		(in years)
Type of award:
Stock options	$	165,361		2.93
Restricted stock and restricted stock units		51,004		2.72
ESPP share issuances		2,892		0.49

        The following table summarizes information about stock options outstanding and exercisable at March 31, 2012:

	Options Outstanding						Options Exercisable
Range of Exercise Prices	Number Outstanding		Weighted-average Remaining Contractual Life		Weighted-average Exercise Price		Number Exercisable		Weighted-average Exercise Price
	(in thousands)		(in years)		(per share)		(in thousands)		(per share)
$9.07–$20.00		2,352		2.98	$	15.52		2,352	$	15.52
$20.01–$30.00		1,793		6.73		29.05		1,304		28.80
$30.01–$40.00		16,299		7.53		36.10		8,660		35.23
$40.01–$50.00		403		8.75		44.42		92		44.53
$50.01–$57.27		2,026		9.20		52.18		413		52.82