Stock-based Compensation Expense and Share Repurchase (Tables)

6 Months Ended

Jun. 30, 2018

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

Stock-based compensation expense by line item

During the three and six months ended June 30, 2018 and 2017, the Company recognized the following stock-based compensation expense:

	Three Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in thousands)
Stock-based compensation expense by type of award:
Stock options	$	28,591		$	27,915		$	54,646		$	54,896
Restricted stock and restricted stock units (including PSUs)	51,497			43,906			101,915			84,651
ESPP share issuances	2,428			2,246			4,556			4,310
Stock-based compensation expense related to inventories	(80		)	(972		)	(545		)	(1,323		)
Total stock-based compensation included in costs and expenses	$	82,436		$	73,095		$	160,572		$	142,534
Stock-based compensation expense by line item:
Cost of sales	$	1,191		$	513		$	2,004		$	970
Research and development expenses	51,612			43,832			100,100			88,669
Sales, general and administrative expenses	29,633			28,750			58,468			52,895
Total stock-based compensation included in costs and expenses	$	82,436		$	73,095		$	160,572		$	142,534

Unrecognized stock-based compensation expense, net of estimated forfeitures

The following table sets forth the Company’s unrecognized stock-based compensation expense as of June 30, 2018, by type of award and the weighted-average period over which that expense is expected to be recognized:

	As of June 30, 2018
	Unrecognized Expense		Weighted-average Recognition Period
	(in thousands)		(in years)
Type of award:
Stock options	$	169,237	2.65
Restricted stock and restricted stock units (including PSUs)	$	343,132	2.57
ESPP share issuances	$	5,777	0.63

Stock options outstanding and exercisable

The following table summarizes information about stock options outstanding and exercisable as of June 30, 2018:

	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)
$26.73–$40.00	707	1.37	$	34.48	707	$	34.48
$40.01–$60.00	557	4.01	$	49.57	557	$	49.57
$60.01–$80.00	615	5.75	$	75.16	603	$	75.15
$80.01–$100.00	3,441	7.70	$	89.36	1,336	$	90.09
$100.01–$120.00	874	6.61	$	109.28	613	$	109.17
$120.01–$140.00	1,034	7.13	$	130.42	702	$	130.36
$140.01–$160.00	1,500	9.59	$	155.52	132	$	155.02
$160.01–$163.74	584	9.02	$	162.94	114	$	162.94
Total	9,312	7.09	$	103.58	4,764	$	87.14