Stockholders' Equity

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Securities Repurchase Program

In June 2020, our board of directors approved a securities repurchase program pursuant to which we may, from time to time, repurchase up to $500.0 million of our common stock and/or convertible notes, through open market purchases, block trades, and/or privately negotiated transactions or pursuant to Rule 10b5-1 plans, in compliance with applicable securities laws and other legal requirements. The timing, volume, and nature of the repurchases will be determined by management based on the capital needs of the business, market conditions, applicable legal requirements, and other factors. The repurchase program will end on December 31, 2021. There were no securities repurchased during the three months ended September 30, 2020.

Share-based Compensation Expense

Total share-based compensation expense recorded for employees and non-employees is as follows (in thousands):


	Three Months Ended September 30,						Nine Months Ended September 30,
	2020		2019		2020		2019
Cost of revenues	$	262	$	96	$	644	$	295
Research and development	8,433		5,741		23,044		15,876
Sales and marketing	2,431		1,843		7,053		5,405
General and administrative	10,403		9,185		28,668		25,779
Total share-based compensation expense	$	21,529	$	16,865	$	59,409	$	47,355

RSU and PSU Activity

Activity for RSUs and PSUs is as follows:


	RSUs and PSUs Outstanding
	Shares Outstanding	Weighted Average Grant Date Fair Value
Balance at December 31, 2019	6,909,530	$	24.04
Granted	2,462,160	43.54
Released	(3,591,076)	18.89
Canceled	(409,544)	30.57
Balance at September 30, 2020	5,371,070	$	35.92

As of September 30, 2020, our total unrecognized share-based compensation expense related to RSUs and PSUs was approximately $122.8 million, which will be recognized over the remaining weighted-average vesting period of approximately 2.0 years.