Quarterly report pursuant to Section 13 or 15(d)

Note 3 - Income Taxes (Details Textual)

v3.8.0.1
Note 3 - Income Taxes (Details Textual) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended 12 Months Ended
Dec. 22, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Jun. 30, 2019
Jun. 30, 2018
Effective Income Tax Rate Reconciliation, Percent   16.00% 36.90% 23.50% 36.70%    
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent 35.00% 23.50%   28.00%      
Effective Income Tax Rate Reconciliation, Remeasurement of Deferred Tax Assets and Liabilities, Amount   $ 2.6   $ 2.6      
Effective Income Tax Rate Reconciliation, Remeasurement of Deferred Tax Assets and Liabilities, Percent   14.60%   8.80%      
Scenario, Forecast [Member]              
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent           21.00% 28.00%
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Earliest Tax Year [Member]              
Income Tax Examination, Year under Examination       2013      
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Latest Tax Year [Member]              
Income Tax Examination, Year under Examination       2016