Stock-Based Compensation (Tables)

3 Months Ended

Jun. 30, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation Recognized

The following table summarizes stock-based compensation expense by financial statement line item in the Company’s condensed consolidated statements of operations for the three months ended June 30, 2017 and 2016:

	For the Three Months Ended June 30,
		2017		2016
	(in $000's)
Cost of product revenue	$	359	$	299
Research and development		1,339		1,255
Selling, general and administrative		6,958		6,843
	$	8,656	$	8,397

Summary of Stock Option Activity

The following table summarizes the stock option activity for the three months ended June 30, 2017:

						Weighted
				Weighted		Average		Aggregate
				Average		Remaining		Intrinsic
	Options			Exercise		Contractual		Value
	(in thousands)			Price		Term (years)		(in thousands)
Outstanding at beginning of period		1,646		$	32.09		5.46
Granted		123			134.24
Exercised		(223	)		15.92
Cancelled and expired		(22	)		109.07
Outstanding at end of period		1,524		$	41.62		5.78	$	154,937
Exercisable at end of period		1,147		$	22.95		4.76	$	138,019
Options vested and expected to vest at end of period		1,487		$	40.93		5.72	$	152,210

Summary of Weighted Average Grant-Date Fair Values And Weighted Average Assumptions Used to Calculate Fair Value of Options Granted

The weighted average grant-date fair values and weighted average assumptions used in the calculation of fair value of options granted during the three months ended June 30, 2017 and 2016 was as follows:

	For the Three Months Ended June 30,
		2017			2016
Weighted average grant-date fair value	$	49.04		$	40.33
Valuation assumptions:
Risk-free interest rate		1.84	%		1.38	%
Expected option life (years)		4.07			4.13
Expected volatility		43.7	%		49.8	%

Summary of Restricted Stock Units Activity

The following table summarizes activity of restricted stock units for the three months ended June 30, 2017:

	Number of Shares			Weighted Average Grant Date Fair Value
	(in thousands)			(per share)
Restricted stock units at beginning of period		1,056		$	80.50
Granted		271		$	134.53
Vested		(319	)	$	50.32
Forfeited		(56	)	$	99.37
Restricted stock units at end of period		952		$	104.90