Note 13 - Stock Option and Retirement Plans - Changes to the Current Estimate of the Vesting Percentage and Related Expense (Details) (Parentheticals) - Performance Shares [Member] - BI-SAM Technologies [Member]	1 Months Ended	6 Months Ended
	Jun. 30, 2017	Feb. 28, 2019
Share-based Compensation Award, Tranche One [Member]
Vesting percentage	40.00%	0.00%
Share-based Compensation Award, Tranche Two [Member]
Vesting percentage	20.00%	80.00%
Share-based Compensation Award, Tranche Three [Member]
Vesting percentage		90.00%
Share-based Compensation Award, Tranche Four [Member]
Vesting percentage		100.00%