Note 14 - Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Sep. 30, 2017	Mar. 31, 2019	Jun. 30, 2019
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	34.00%
Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Lighting Reporting Unit [Member]
Deferred Tax Assets, Increase During Period, Impairment of Goodwill	$ 10.7	$ 4.8