Note 6 - Accrued Expenses - Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2016
Accrued Expenses:
Compensation and benefits	$ 8,388	$ 9,759
Customer prepayments	1,636	1,061
Accrued sales commissions	1,886	2,314
Accrued warranty	6,721	7,560	$ 7,534	$ 5,069
Other accrued expenses	4,825	5,375
Total Accrued Expenses	$ 23,456	$ 26,069