v3.6.0.2

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of stock option activity

		Outstanding Options
									Weighted-
						Weighted-			Average
		Shares				Average			Remaining		Aggregate
		Available for		Number of		Exercise			Contractual		Intrinsic
(in thousands, except for contractual life and exercise price)		Grant		Shares		Price			Life		Value
									(In years)
Balance at December 31, 2015		3,743		9,316		$	3.96		8.31		$	63,713
Additional shares authorized		2,014		—
Options granted		(2,558)		2,558		$	10.23
Options exercised		—		(1,915)		$	1.88
Options forfeited		916		(916)		$	8.28
Balance at December 31, 2016		4,115		9,043		$	5.72		7.55		$	55,396
Exercisable at December 31, 2016				5,054		$	3.10		6.51		$	43,938
Vested and expected to vest at December 31, 2016				9,039		$	5.72		7.55		$	55,386

Restricted stock units

					Weighted-Average Grant Date
		Shares			Fair Value
Balance at December 31, 2015			—		$	—
Granted			212		$	9.76
Vested			(40)		$	9.59
Canceled/forfeited			(13)		$	9.81
Balance at December 31, 2016			159		$	9.80

Summary of stock-based compensation expenses

		Year ended December 31,
		2016									2015									2014
		Employee			Non-Employee			Total			Employee			Non-Employee			Total			Employee			Non-Employee			Total
		(in thousands)
Cost of revenues		$	651		$	(10)		$	641		$	351		$	241		$	592		$	262		$	29		$	291
Research and development			2,829			24			2,853			1,566			9			1,575			1,563			30			1,593
Selling, general and administrative			6,837			270			7,107			4,993			166			5,159			3,180			93			3,273
Total		$	10,317		$	284		$	10,601		$	6,910		$	416		$	7,326			5,005		$	152		$	5,157

Employee stock options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions used in valuation of fair value of employee stock options

		Year ended December 31,
		2016						2015						2014
Expected term		5.1		—	5.2			5.6		—	10.0			4.9 — 7.1
Expected volatility		62.2	%	—	72.5	%		69.7	%	—	78.8	%		73.4	%	—	87.0	%
Expected dividend rate					0	%					0	%					0	%
Risk-free interest rate		0.97	%	—	1.92	%		1.56	%	—	2.32	%		1.65	%	—	2.04	%

Non-employee stock options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions used in valuation of fair value of employee stock options

		Year ended December 31,
		2016						2015						2014
Expected term		2.7		—	3.2			4.9		—	9.8			4.4  — 10.0
Expected volatility		50.9	%	—	72.6	%		70.2	%	—	75.4	%		71.9	%	—	80.2	%
Expected dividend rate					0	%					0	%					0	%
Risk-free interest rate		0.68	%	—	1.38	%		1.74	%	—	2.24	%		1.41	%	—	2.61	%

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- Definition

Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed.

+ References

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Tabular disclosure of the number, aggregate intrinsic value (except for nonpublic entities), and weighted-average remaining contractual term for both restricted stock units outstanding and restricted stock units fully vested and expected to vest at the date of the latest statement of financial position.

+ References

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Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year.

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