Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2020

Share-based Payment Arrangement [Abstract]

Schedule of Shares Available for Grant and Stock Option Activity

Stock option activity under the Plans is as follows:

			Options Outstanding
	Shares Available for Grant		Shares Subject to Options Outstanding		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
	(in thousands, except per share data and years)
Balance as of December 31, 2019	8,160		14,020		$	1.85	6.7	$	325,474
Shares authorized	3,812		—
Exercised	—		(1,247	)	$	1.38
Forfeited/cancelled	144		(144	)	$	1.88
Restricted stock units and PSUs granted	(726	)	—
Restricted stock units and PSUs forfeited	101		—
Restricted stock units and PSUs withheld for income taxes	375		—
Balance as of March 31, 2020	11,866		12,629		$	1.89	6.4	$	336,424
Vested and exercisable as of March 31, 2020			9,176		$	1.53	6.0	$	247,727

Schedule of Restricted Stock Awards

Restricted Stock Awards

	Shares		Weighted- Average Grant Date Fair Value
	(in thousands, except per share data)
Unvested balance, December 31, 2019	736		$	9.76
Vested	(122	)	$	9.76
Unvested balance, March 31, 2020	614		$	9.76

Schedule of Restricted Stock Units

	Restricted Stock Units, Performance RSUs and PSUs		Weighted- Average Grant Date Fair Value
	(in thousands, except per share data)
Balance as of December 31, 2019	4,708		$	11.31
Granted	726		$	24.41
Released	(620	)	$	8.79
Forfeited	(101	)	$	17.95
Balance as of March 31, 2020	4,713		$	13.52

Summary of Stock-Based Compensation Expense

Stock-based compensation expense in the condensed consolidated statements of operations is summarized as follows:

	Three Months Ended March 31,
	2020		2019
	(in thousands)
Cost of revenue	$	92	$	6
Research and development expenses	2,216		361
Sales and marketing expenses	2,052		219
General and administrative expenses	3,703		4,924
Total stock-based compensation expense	$	8,063	$	5,510