Note 14 - Income Taxes (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	35.00%
Tax Cuts and Jobs Act, Incomplete Accounting, Change in Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense	$ 0.1	$ 3.2
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	9.0
Tax Credit Carryforward, Amount	$ 1.6
Open Tax Year	2016
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 4.9
Open Tax Year	2015