Note 6 - Accrued Expenses - Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019
Accrued Expenses:
Compensation and benefits	$ 3,974	$ 5,319
Customer prepayments	1,898	1,768
Accrued sales commissions	2,248	1,301
Accrued warranty	7,666	7,687
Other accrued expenses	6,085	5,136
Total Accrued Expenses	$ 21,871	$ 21,211