Stockholders' Equity (Tables)

9 Months Ended

Sep. 29, 2018

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

Schedule of stock option activity

Stock option activity under the equity incentive plans was as follows (in thousands, except per share amounts):

	Stock Options Outstanding
	Number of Shares Subject to Stock Options		Weighted– Average Exercise Price		Aggregate Intrinsic Value (1)
Balance—December 31, 2017	21,386		$	3.01
Granted	—		—
Exercised	(2,339	)	2.33
Forfeited or canceled	(582	)	7.05
Balance—September 29, 2018	18,465		2.97		$	50,236
Stock options vested and expected to vest—September 29, 2018	18,455		2.97		50,219
Stock options exercisable—September 29, 2018	16,758		2.72		48,539

⁽¹⁾ The aggregate intrinsic values of stock options outstanding, exercisable, vested and expected to vest as of September 29, 2018 were calculated as the difference between the exercise price of the stock options and the fair value of the Class A common stock of $5.35 as of September 29, 2018.

Schedule of restricted stock unit activity

RSU activity under the equity incentive plans was as follows (in thousands, except per share amounts):

	RSUs Outstanding		Weighted- Average Grant Date Fair Value
Unvested balance—December 31, 2017	19,188		$	9.13
Granted	13,709		5.11
Vested	(7,806	)	8.42
Forfeited or canceled	(4,389	)	8.07
Unvested balance—September 29, 2018	20,702		$	6.96

Schedule of stock-based compensation expense

Total stock-based compensation expense recognized was as follows (in thousands):

	Three Months Ended				Nine Months Ended
	September 29, 2018		September 30, 2017		September 29, 2018		September 30, 2017
Cost of revenue	$	1,999	$	1,379	$	5,129	$	2,889
Research and development	14,097		12,947		43,858		40,280
Sales and marketing	3,638		3,679		10,996		11,301
General and administrative	4,381		4,792		13,630		12,786
Total stock-based compensation expense	$	24,115	$	22,797	$	73,613	$	67,256