Stock-based Compensation Expense (Tables)

3 Months Ended

Mar. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-based compensation expense by line item

During the three months ended March 31, 2014 and 2013, the Company recognized the following stock-based compensation expense:

	Three Months Ended March 31,
	2014			2013
	(in thousands)
Stock-based compensation expense by type of award:
Stock options	$	25,127		$	19,674
Restricted stock and restricted stock units	18,993			9,378
ESPP share issuances	2,667			2,522
Less stock-based compensation expense capitalized to inventories	(207		)	(299		)
Total stock-based compensation expense included in costs and expenses	$	46,580		$	31,275
Stock-based compensation expense by line item:
Research and development expenses	$	32,900		$	19,349
Sales, general and administrative expenses	13,680			11,926
Total stock-based compensation expense included in costs and expenses	$	46,580		$	31,275

Unrecognized stock-based compensation expense, net of estimated forfeitures

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

	As of March 31, 2014
	Unrecognized Expense, Net of Estimated Forfeitures		Weighted-average Recognition Period
	(in thousands)		(in years)
Type of award:
Stock options	$	183,052	2.50
Restricted stock and restricted stock units	$	120,440	2.21
ESPP share issuances	$	3,416	0.51

Stock options outstanding and exercisable

The following table summarizes information about stock options outstanding and exercisable at March 31, 2014:

	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)
$9.09–$20.00	407	2.20	$15.42	407	$15.42
$20.01–$30.00	908	5.62	$29.44	696	$29.30
$30.01–$40.00	5,846	5.10	$36.35	4,199	$35.84
$40.01–$50.00	3,840	8.60	$46.32	816	$46.59
$50.01–$60.00	1,569	7.00	$53.86	851	$54.41
$60.01–$70.00	79	8.84	$65.57	18	$63.81
$70.01–$80.00	2,029	9.81	$77.19	15	$77.66
$80.01–$88.18	1,400	9.30	$83.12	316	$82.38
Total	16,078	7.06	$48.89	7,318	$39.60