Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

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

Stock-Based Compensation Expense for Options Granted, Restricted Stock and Stock Purchase Rights as Reflected in Statement of Operations

Stock-based compensation expense for options and restricted stock awards (“RSAs”) is reflected in the condensed consolidated statements of operations and comprehensive loss as follows:

	THREE MONTHS ENDED   SEPTEMBER 30,				NINE MONTHS ENDED   SEPTEMBER 30,
(in thousands)	2017		2016		2017		2016
Selling, general and administrative	$	4,995	$	3,406	$	14,032	$	9,295
Research and development	1,562		693		4,040		2,219
Total	$	6,557	$	4,099	$	18,072	$	11,514

Schedule of Stock Options Activity

The following table summarizes the stock option activity under the Plans:

	NUMBER OF SHARES		WEIGHTED AVERAGE EXERCISE PRICE		WEIGHTED AVERAGE REMAINING CONTRACTUAL LIFE (YEARS)	AGGREGATE INTRINSIC VALUE (000’s)
Options outstanding at December 31, 2016	5,255,930		$	14.34
Granted	1,203,459		46.30
Exercised	(202,134	)	11.05
Canceled	(19,296	)	32.82
Options outstanding at September 30, 2017	6,237,959		$	20.56	7.3	$	176,569
Options exercisable at September 30, 2017	3,954,715		$	12.57	6.4	$	142,558

Restricted Stock and Restricted Stock Units Activity

The following table summarizes the RSA activity under the Plans:

	NUMBER OF SHARES		WEIGHTED AVERAGE FAIR VALUE PER SHARE
Nonvested RSAs at December 31, 2016	164,194		$	19.87
Granted	332,512		47.61
Vested	(54,591	)	20.47
Canceled	(2,566	)	43.90
Nonvested RSAs at September 30, 2017	439,549		$	40.64