Note 2 - Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Restricted Cash
Restricted Cash	$ 1.5	$ 1.3
Restricted Cash, Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherCurrentAssets	us-gaap:OtherCurrentAssets