Stock-Based Compensation (Tables)

3 Months Ended

Jun. 30, 2020

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, 2020 and 2019:

	For the Three Months Ended June 30,
		2020		2019
	(in $000's)
Cost of product revenue	$	705	$	841
Research and development		1,442		1,883
Selling, general and administrative		7,151		10,397
	$	9,298	$	13,121

Summary of Stock Option Activity

The following table summarizes the stock option activity for the three months ended June 30, 2020:

						Weighted
				Weighted		Average		Aggregate
				Average		Remaining		Intrinsic
	Options			Exercise		Contractual		Value
	(in thousands)			Price		Term (years)		(in thousands)
Outstanding at beginning of period		869		$	112.03		5.30
Granted		64			220.13
Exercised		(31	)		32.12
Cancelled and expired		(4	)		238.28
Outstanding at end of period		898		$	121.95		5.53	$	119,849
Exercisable at end of period		707		$	87.62		4.60	$	116,169
Options vested and expected to vest at end of period		896		$	121.96		5.53	$	119,698

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

	For the Three Months Ended June 30,
		2020			2019
Weighted average grant-date fair value	$	75.75		$	96.30
Valuation assumptions:
Risk-free interest rate		0.31	%		2.03	%
Expected option life (years)		4.22			4.14
Expected volatility		42.8	%		42.3	%

Restricted Stock Units

Summary of Restricted Stock Units Activity

The following table summarizes activity of restricted stock units for the three months ended June 30, 2020:

	Number of Shares			Weighted Average Grant Date Fair Value
	(in thousands)			(per share)
Restricted stock units at beginning of period		320		$	263.92
Granted		164			247.01
Vested		(124	)		229.22
Forfeited		(100	)		267.72
Restricted stock units at end of period		260		$	268.13

Summary of Assumptions Used To Value Awards And Estimated Grant-Date Fair Value

The table below sets forth the assumptions used to value the awards and the estimated grant-date fair value:

Risk-free interest rate		0.2	%
Expected volatility		35.5	%
Dividend yield		—
Remaining performance period (years)	1.9 - 2.9
Estimated fair value per share	$347.05 - $349.28
Target performance (number of shares)		30,781