Stock-based Compensation Expense

3 Months Ended

Mar. 31, 2015

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

Stock-based Compensation Expense

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, stock options that vest upon the earlier of the satisfaction of (a) performance conditions or (b) a service condition and restricted stock and restricted stock units that vest upon the satisfaction of (i) a performance condition and (ii) a service condition. In addition, the Company issued pursuant to a retention program restricted stock awards to certain members of senior management that will vest upon the satisfaction of both (i) a performance condition and (ii) a service condition. In addition, the Company issues shares pursuant to an employee stock purchase plan ("ESPP").

Effective for equity awards granted on or after February 5, 2014, the Company provides to employees who have rendered significant service to the Company and meet certain age requirements, partial or full acceleration of vesting of these equity awards, subject to certain conditions, upon a termination of employment other than for cause.  Less than 5% of the Company’s employees were eligible for partial or full acceleration of any of their equity awards as of March 31, 2015.  The Company recognizes stock-based compensation expense related to these awards over the service period from the date of grant until the qualified employees become eligible for partial or full acceleration of vesting.

During the three months ended March 31, 2015 and 2014, the Company recognized the following stock-based compensation expense included in loss from continuing operations:

	Three Months Ended March 31,
	2015			2014
	(in thousands)
Stock-based compensation expense by type of award:
Stock options	$	28,959		$	25,127
Restricted stock and restricted stock units	27,169			18,993
ESPP share issuances	2,140			2,667
Less stock-based compensation expense capitalized to inventories	(884		)	(207		)
Total stock-based compensation included in costs and expenses	$	57,384		$	46,580
Stock-based compensation expense by line item:
Research and development expenses	$	38,217		$	32,900
Sales, general and administrative expenses	19,167			13,680
Total stock-based compensation included in costs and expenses	$	57,384		$	46,580

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, 2015
	Unrecognized Expense, Net of Estimated Forfeitures		Weighted-average Recognition Period
	(in thousands)		(in years)
Type of award:
Stock options	$	199,256	2.31
Restricted stock and restricted stock units	$	201,465	2.88
ESPP share issuances	$	2,205	0.45

The following table summarizes information about stock options outstanding and exercisable at March 31, 2015:

	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)
$17.16–$20.00	165	2.51	$	18.69	165	$	18.69
$20.01–$40.00	3,207	4.24	$	34.97	2,711	$	34.73
$40.01–$60.00	3,339	7.33	$	48.55	1,499	$	50.27
$60.01–$80.00	1,837	8.59	$	76.07	492	$	74.88
$80.01–$100.00	2,232	8.70	$	90.29	542	$	86.07
$100.01–$120.00	1,898	9.84	$	109.23	1	$	110.59
$120.01–$125.63	4	9.82	$	125.63	—	$	—
Total	12,682	7.28	$	65.17	5,410	$	47.36