Note 9 - Equity Compensation - Summary of Restricted Stock Units Activity (Details) - $ / shares	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Granted (in shares)	972,900	794,537
Granted (in dollars per share)	$ 1.48	$ 1.73
Restricted Stock Units (RSUs) [Member]
Unvested (in shares)	169,397
Unvested (in dollars per share)	$ 8.03
Granted (in shares)
Granted (in dollars per share)		$ 5.92
Vested (in shares)	(113,523)
Vested (in dollars per share)	$ 8.14
Forfeited (in shares)	(22,832)
Forfeited (in dollars per share)	$ 7.91
Unvested (in shares)	33,042	169,397
Unvested (in dollars per share)	$ 7.72	$ 8.03

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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