Note 8 - Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Jun. 30, 2019
Cash and cash equivalents	$ 3,180	$ 5,326
Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	3,180	5,326
Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents