Note 14 - Severance Costs (Details Textual) - USD ($)	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Apr. 23, 2018
Severance Costs	$ 1,900,000	$ 523,000	$ 469,000
Former CEO [Member]
Postemployment Benefits Liability, Total				$ 1,772,000
Postemployment Benefits Liability, Current				640,000
Postemployment Benefits Liability, Noncurrent				$ 1,132,000

For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement that is payable within one year of the balance sheet date.

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The carrying amount as of the balance sheet date of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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