Note 4 - Inventories (Details Textual) - USD ($)	3 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016
Cost of Sales [Member]
Inventory, LIFO Reserve, Effect on Income, Net	$ 0	$ 100,000
Inventory Difference Using FIFO Basis	28,800,000		$ 28,800,000
LIFO Inventory Amount	$ 11,500,000		$ 10,500,000