Note 11 - Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Effective Income Tax Rate Reconciliation, Percent, Total	40.70%	10.40%	20.90%	3.80%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Tax Cuts and Jobs Act, Interest Deduction Limits, Percentage of Adjusted Taxable Income Allowed	30.00%		30.00%
Deferred Tax Asset, Interest Carryforward	$ 8.9		$ 8.9
Foreign Income Tax Expense (Benefit), Continuing Operations, Total			6.6
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount			1.9
State and Local Income Tax Expense (Benefit), Continuing Operations, Total			1.2
Foreign Tax Authority [Member] | Kenya Revenue Authority [Member]
Unrecognized Tax Benefits, Income Tax Penalties Accrued	$ 77.0		$ 77.0