Stock-based Awards (Details - Options) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Additional disclosure
Stock-based compensation expense	$ 6,454	$ 15,556	$ 12,631	$ 24,191
Options
Number of Options
Outstanding at the beginning of period (in shares)			10,625,980
Granted (in shares)			1,713,111
Exercised (in shares)			(3,166)
Canceled/forfeited (in shares)			(1,596,381)
Outstanding at the end of the period (in shares)	10,739,544		10,739,544		10,625,980
Weighted-Average Exercise Price
Outstanding at the beginning of period (in dollars per share)			$ 11.22
Granted (in dollars per share)			2.66
Exercised (in dollars per share)			0.83
Canceled/forfeited (in dollars per share)			12.28
Outstanding at the end of the period (in dollars per share)	$ 9.70		$ 9.70		$ 11.22
Additional disclosure
Weighted average remaining contractual life (in years)			5 years 3 months 18 days		5 years 2 months 12 days
Remaining stock-based compensation expense for unvested awards	$ 9,500		$ 9,500
Weighted average period over which remaining stock based compensation expense for unvested awards is expected to be recognized			2 years 3 months 18 days
Stock-based compensation expense	$ 1,500	$ 6,900	$ 3,100	$ 10,000