Note 11 - Commitments and Contingencies - Redeemable Non-controlling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Balance			$ 16,112
Net income attributable to noncontrolling interest	$ (156)	$ 565	(956)	$ 834
Balance	7,940		7,940
Natural Habitat, Inc [Member]
Balance	9,970	6,771	16,112	6,502
Net income attributable to noncontrolling interest	(156)	565	(956)	834
Fair value adjustment of put option	(1,874)	0	(7,216)	0
Balance	$ 7,940	$ 7,336	$ 7,940	$ 7,336