Income Taxes - Deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018
Deferred tax assets related to:
U.S. and foreign net operating loss carryforwards	$ 16,017	$ 18,297
Accrued compensation	1,262	1,117
Unrealized gain/loss on investments	1,828	0
Partnership investment	237	0
U.S. credit carryforwards	1,225	1,726
Stock compensation	190	680
Acquisition costs	75	0
Other	76	709
Deferred tax assets	20,910	22,529
Valuation allowance	(20,435)	(21,554)
Total deferred tax assets	$ 475	$ 975