Note 14 - Share-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Stock options outstanding, beginning of period (in shares)	13,788,475
Balance, weighted average exercise price, beginning of period (in dollars per share)	$ 0.15
Stock options outstanding, weighted average remaining contractual term (Year)	8 years 255 days	6 years 219 days
Options assumed in the Merger (in shares)	80,000
Options assumed in the Merger, weighted average exercise price (in dollars per share)	$ 0.22
Stock options granted (in shares)	32,177,804
Stock options granted (in dollars per share)	$ 0.15
Stock options exercised (in shares)	(161,521)
Stock options exercised, weighted average exercise price (in dollars per share)	$ 0.14
Stock options cancelled (in shares)	(3,981,030)
Stock options cancelled, weighted average exercise price (in dollars per share)	$ 0.15
Stock options outstanding, end of period (in shares)	41,903,728	13,788,475
Balance, weighted average exercise price, end of period (in dollars per share)	$ 0.15	$ 0.15
Stock options outstanding, aggregate intrinsic value	$ 39,046
Exercisable options outstanding (in shares)	9,306,443
Stock options exercisable, weighted average exercise price (in dollars per share)	$ 0.14
Stock options exercisable, weighted average remaining contractual term (Year)	5 years 255 days
Stock options exercisable, aggregate intrinsic value	$ 8,731
Vested and expected to vest options outstanding (in shares)	40,273,850
Stock options vested and expected to vest, weighted average exercise price (in dollars per share)	$ 0.15
Stock options vested and expected to vest, weighted average remaining contractual term (Year)	8 years 219 days
Stock options vested and expected to vest, aggregate intrinsic value	$ 37,530