Employee Benefit Plans and Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Company's Stock Option and Restricted Stock Unit Activity

The following table summarizes the Company’s stock option, RSU and PSU activities during the nine months endedSeptember 30, 2016 (in thousands, except per share amounts):

			Stock Options Outstanding				Restricted Stock Units Outstanding*
	Shares Available for Grant		Number of Shares		Weighted Average Exercise Price		Number of Units		Weighted Average Grant Date Fair Value
Balance at December 31, 2015	6,150		5,674		$	6.56	2,182		$	6.99
Authorized	2,000		—		—		—		—
Granted	(5,046	)	916		3.14		3,053		3.55
Options exercised	—		(148	)	4.80		—		—
Shares released	—		—		—		(1,269	)	6.82
Forfeited or cancelled	1,833		(1,388	)	6.44		(304	)	5.73
Balance at September 30, 2016	4,937		5,054		$	6.03	3,662		$	4.18

Summary of Stock Options Outstanding

The following table summarizes information about stock options outstanding as of September 30, 2016 (in thousands, except per share amounts):

	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Vested and expected to vest	4,826	$	6.08	4.0	$	3,015
Exercisable	3,063	6.63		3.0	750

Summary of Restricted Stock Units Outstanding

The following table summarizes information about RSUs and PSUs outstanding as of September 30, 2016 (in thousands, except per share amounts):

	Number of Shares Underlying Restricted Stock Units	Weighted Average Remaining Vesting Period (Years)	Aggregate Fair Value
Vested and expected to vest	2,740	0.9	$	16,250

Schedule of Defined Benefit Plans Obligations

hanges to the Company’s defined benefit pension plan obligations are shown below (in thousands):

	September 30, 2016
Projected benefit obligation:
Acquired from TVN acquisition	$	5,907
Service cost	164
Interest cost	68
Foreign currency translation adjustment	102
As of September 30, 2016	$	6,241
Presented on the Condensed Consolidated Balance Sheets under:
Current portion (presented under “Accrued liabilities”)	$	248
Long-term portion (presented under “Other non-current liabilities”)	$	5,993

Schedule of Assumptions Used - Employee Benefit Plans Obligation

The following assumptions were used in determining the Company’s pension obligation:

	September 30, 2016
Discount rate	2.0	%
Mobility rate	2.2	%
Salary progression rate	2.0	%

Schedule of Expected Benefit Payments

Future benefits expected to be paid in each of the next five years, and in the aggregate for the five year period thereafter are as follows (in thousands):

Years ending December 31,
2016 (remaining three months)	$	24
2017	117
2018	227
2019	366
2020	433
2021 - 2025	2,310
	$	3,477

Summary of Stock-Based Compensation Expense

Stock-based Compensation

The following table summarizes stock-based compensation expense for all plans (in thousands):

	Three months ended				Nine months ended
	September 30, 2016		October 2, 2015		September 30, 2016		October 2, 2015
Stock-based compensation in:
Cost of revenue	$	360	$	433	$	1,011	$	1,383
Research and development expense	771		1,074		2,581		3,249
Selling, general and administrative expense	1,549		2,320		4,950		7,213
Total stock-based compensation in operating expense	2,320		3,394		7,531		10,462
Total stock-based compensation	$	2,680	$	3,827	$	8,542	$	11,845

Valuation Assumptions for Stock Options

	Employee Stock Options
	Three months ended				Nine months ended
	September 30, 2016		October 2, 2015		September 30, 2016		October 2, 2015
Expected term (years)	4.30		4.60		4.30		4.70
Volatility	39	%	37	%	36	%	38	%
Risk-free interest rate	1.0	%	1.5	%	1.4	%	1.6	%
Expected dividends	0.0	%	0.0	%	0.0	%	0.0	%

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions

	ESPP Purchase Period Ending
	December 31, 2016		July 1, 2016		December 31, 2015		June 30, 2015
Expected term (years)	0.50		0.50		0.50		0.50
Volatility	62	%	54	%	32	%	35	%
Risk-free interest rate	0.4	%	0.4	%	0.1	%	0.1	%
Expected dividends	0.0	%	0.0	%	0.0	%	0.0	%
Estimated weighted average fair value per share at purchase date	$0.98		$1.19		$1.64		$1.75