Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2020

Stock-Based Compensation

Summary of restricted stock award activity

		Weighted
		average
	Number	grant-date
	of shares	fair value
Outstanding at December 31, 2019	1,213,581	$	37.69
Granted	388,108		67.91
Vested	(253,683)		45.23
Forfeited	(33,371)		54.96
Outstanding at March 31, 2020	1,314,635	$	44.72

Schedule of weighted average assumptions for employee grants

	Three Months Ended
	March 31,
Valuation assumptions:	2020		2019
Expected volatility	56.10	%	69.70	%
Expected term (years)	5.25		6.02
Risk-free interest rate	1.22	%	2.50	%
Dividend yield	—		—

Summary of stock option activity

				Weighted
		Weighted		average
		average		remaining	Aggregate
	Number	exercise		contractual	intrinsic
	of shares	price		term	value
Outstanding at December 31, 2019	2,755,343	$	25.10
Granted	5,000		68.10
Exercised	(117,755)		11.09
Forfeited	(15,095)		49.88
Outstanding at March 31, 2020	2,627,493	$	25.66	6.7	$	73,345
Options vested and expected to vest at March 31, 2020	2,627,493	$	25.66	6.7	$	73,345
Exercisable at March 31, 2020	1,703,465	$	17.11	5.9	$	60,994

Schedule of recorded stock-based compensation expense related to stock options

	Three Months Ended
	March 31,
	2020		2019
Cost of revenue - product	$	182	$	309
Cost of revenue - service		763		984
Research and development		1,409		2,282
Sales and marketing		528		987
General and administrative		4,255		2,290
Total stock-based compensation expense	$	7,137	$	6,852