Note 18 - Fair Value of Financial Instruments - Securities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Marketable equity securities	$ 29,521	$ 27,549
Fair Value, Inputs, Level 1 [Member]
Marketable equity securities	29,521	27,549
Fair Value, Inputs, Level 2 [Member]
Marketable equity securities
Fair Value, Inputs, Level 3 [Member]
Marketable equity securities