| Note 2 - Selected Balance Sheet Data - Inventories (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Jun. 30, 2017 | 
|---|---|---|
| Raw materials | $ 25,401 | $ 22,074 | 
| Finished goods | 42,879 | 38,077 | 
| Inventories, net | $ 68,280 | $ 60,151 | 
| X | ||||||||||
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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