Note 13 - Stock Option and Retirement Plans - Changes to the Current Estimate of the Vesting Percentage and Related Expense (Details) (Parentheticals) - Performance Shares [Member]	1 Months Ended		6 Months Ended
	Jun. 30, 2017	Jan. 31, 2017	Feb. 28, 2018
Share-based Compensation Award, Tranche One [Member] | Vermilion Holdings Limited [Member]
Vesting percentage		40.00%	0.00%
Share-based Compensation Award, Tranche One [Member] | BI-SAM Technologies [Member]
Vesting percentage	40.00%		0.00%
Share-based Compensation Award, Tranche Two [Member] | Vermilion Holdings Limited [Member]
Vesting percentage		20.00%	100.00%
Share-based Compensation Award, Tranche Two [Member] | BI-SAM Technologies [Member]
Vesting percentage	20.00%		80.00%
Share-based Compensation Award, Tranche Three [Member] | BI-SAM Technologies [Member]
Vesting percentage			90.00%
Share-based Compensation Award, Tranche Four [Member] | BI-SAM Technologies [Member]
Vesting percentage			100.00%