Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Stock-Based Compensation

Schedule of weighted average assumptions for employee grants

	Year Ended
	December 31,
Valuation assumptions:	2016		2015		2014
Expected volatility	61.00	%	55.21	%	59.37	%
Expected life (years)	5.69		6.05		6.00
Risk-free interest rate	1.37	%	1.75	%	1.98	%
Dividend yield	—		—		—

Summary of stock option activity

				Weighted
		Weighted		average
		average		remaining	Aggregate
	Number	exercise		contractual	intrinsic
	of shares	price		term	value
Outstanding at January 1, 2014	2,635,827	$	2.20
Granted	259,928		6.01
Exercised	(41,151)		1.42
Forfeited	(9,378)		4.17
Outstanding at December 31, 2014	2,845,226	$	2.56
Granted	365,098		6.42
Exercised	(406,683)		1.04
Forfeited	(11,887)		6.24
Outstanding at December 31, 2015	2,791,754	$	3.27
Granted	479,010		14.56
Exercised	(203,991)		1.32
Forfeited	(7,083)		9.02
Outstanding at December 31, 2016	3,059,690	$	5.14	6.2	$	30,178
Options vested and expected to vest at December 31, 2016	3,059,690	$	5.14	6.2	$	30,178
Exercisable at December 31, 2016	2,214,358	$	3.10	5.4	$	26,314

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

	Year Ended
	December 31,
	2016		2015		2014
Cost of revenue - product	$	191	$	102	$	57
Cost of revenue - service		46		23		3
Research and development		62		25		9
Sales and marketing		138		91		57
General and administrative		3,813		324		128
	$	4,250	$	565	$	254