v3.7.0.1

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

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, 2016		4,115		9,043		$	5.72		7.55		$	55,396
Additional shares authorized		2,107		—
Options granted		(1,568)		1,568		$	10.23
Options exercised		—		(280)		$	3.36
Options forfeited/cancelled		380		(380)		$	10.23
Balance at June 30, 2017		5,034		9,951		$	6.33		7.44		$	46,865
Exercisable at June 30, 2017				5,415		$	3.89		6.25		$	38,550
Vested and expected to vest at June 30, 2017				9,509		$	6.19		7.37		$	46,054

Restricted stock units

				Weighted-
				Average
				Grant Date
(in thousands, except for grant date fair value)		Shares		Fair Value
Balance at December 31, 2016		159		$	9.80
Granted		295		$	10.25
Vested		(51)		$	9.70
Canceled/forfeited		(20)		$	9.64
Balance at June 30, 2017		383		$	10.16

Summary of stock-based compensation expenses

		Three months ended  June 30,
		2017									2016
		Employee			Non-Employee			Total			Employee			Non-Employee			Total
		(in thousands)
Cost of revenues		$	139		$	13		$	152		$	157		$	32		$	189
Research and development			730			—			730			716			1			717
Selling, general and administrative			1,992			3			1,995			1,940			51			1,991
Total		$	2,861		$	16		$	2,877		$	2,813		$	84		$	2,897

		Six months ended June 30,
		2017									2016
		Employee			Non-Employee			Total			Employee			Non-Employee			Total
		(in thousands)
Cost of revenues		$	282		$	1		$	283		$	315		$	7		$	322
Research and development			1,380			—			1,380			1,321			—			1,321
Selling, general and administrative			3,756			1			3,757			3,401			248			3,649
Total		$	5,418		$	2		$	5,420		$	5,037		$	255		$	5,292

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

		Three months ended  June 30,												Six months ended June 30,
		2017						2016						2017						2016
Expected term (years)		5.1		—	5.2			5.1		—	5.2			5.1		—	5.2			5.1		—	5.2
Expected volatility		62.7	%	—	62.9	%		68.5	%	—	69.2	%		62.7	%	—	62.9	%		68.5	%	—	71.0	%
Expected dividend rate					0	%					0	%					0	%					0	%
Risk-free interest rate		1.80	%	—	1.87	%		1.18	%	—	1.24	%		1.80	%	—	1.91	%		1.18	%	—	1.24	%

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

		Three months ended  June 30,												Six months ended June 30,
		2017						2016						2017						2016
Expected term (years)					2.7						2.8						2.7			2.8		—	3.2
Expected volatility					52.2	%					56.5	%		51.7	%	—	52.2	%		56.5	%	—	72.6	%
Expected dividend rate					0	%					0	%					0	%					0	%
Risk-free interest rate					1.50	%					0.68	%		1.42	%	—	1.50	%		0.68	%	—	0.90	%

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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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- Definition

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.

+ References

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-Publisher FASB
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Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

+ References

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