v3.19.3
NET INCOME (LOSS) PER SHARE - Calculation of Basic and Diluted Net Loss Per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Sep. 30, 2019
Sep. 30, 2018
Earnings Per Share [Abstract]                
Net income (loss) $ 29,397 $ (6,740) $ (38,151) $ 19,643 $ (5,906) $ (23,986) $ (15,494) $ (10,249)
Basic shares:                
Weighted-average common shares outstanding (in shares) 427,906     410,095     423,957 403,577
Weighted-average unvested shares (in shares) (782)     (405)     (718) (597)
Weighted-average shares used to compute basic net loss per share (in shares) 427,124     409,690     423,239 402,980
Diluted shares:                
Stock options and restricted stock units 28,549     47,175     0 0
Convertible senior notes 0     6,409     0 0
Common stock warrants 10,372     11,422     0 0
Employee stock purchase plan 54     219     0 0
Weighted-average shares used to compute diluted income (loss) per share (in shares) 466,099     474,915     423,239 402,980
Net income (loss) per share:                
Basic (in USD per share) $ 0.07     $ 0.05     $ (0.04) $ (0.03)
Diluted (in USD per share) $ 0.06     $ 0.04     $ (0.04) $ (0.03)