Subsequent Events	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Events Additional earn-out payment received from sale of a private company investment In January 2019, the Company received proceeds of $1.0 million representing the second earn-out payment from the sale of a private company investment which will be recognized as a gain on sale of assets during the first quarter of 2019. Increase of share reserves under equity incentive plans On January 1, 2019, the number of authorized shares of common stock that may be issued under the 2018 Plan and 2018 ESPP increased by 6,290,894 shares and 1,258,178 shares, respectively, pursuant to the automatic share increase provisions of the plans. 2019 stock-based awards activity In February 2019, the Company granted 2,225,766 stock options and 3,820,944 restricted stock units to its employees, substantially all of which were issued as a part of the Company’s annual stock-based award process. The stock options and restricted stock units granted have vesting restrictions, valuations and contractual lives of a similar nature to those described in Note 7 above. The stock option and restricted stock unit grants result in gross stock-based compensation of $66.3 million.

Subsequent Events

12 Months Ended

Dec. 31, 2018

14. Subsequent Events

Additional earn-out payment received from sale of a private company investment

In January 2019, the Company received proceeds of $1.0 million representing the second earn-out payment from the sale of a private company investment which will be recognized as a gain on sale of assets during the first quarter of 2019.

Increase of share reserves under equity incentive plans

On January 1, 2019, the number of authorized shares of common stock that may be issued under the 2018 Plan and 2018 ESPP increased by 6,290,894 shares and 1,258,178 shares, respectively, pursuant to the automatic share increase provisions of the plans.

2019 stock-based awards activity

In February 2019, the Company granted 2,225,766 stock options and 3,820,944 restricted stock units to its employees, substantially all of which were issued as a part of the Company’s annual stock-based award process. The stock options and restricted stock units granted have vesting restrictions, valuations and contractual lives of a similar nature to those described in Note 7 above. The stock option and restricted stock unit grants result in gross stock-based compensation of $66.3 million.