Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Deferred tax assets
Stock-based compensation	$ 2,505	$ 5,107
Deferred Tax Assets, Deferred Income	2,351	0
Accrued expenses	970	1,650
Inventories	305	433
Compensation accruals	133	261
Depreciation and amortization	320	409
Other	397	1,019
Research and development credit carryforwards	5,048	4,650
Net operating loss carryforwards	64,101	87,502
Total deferred tax assets	76,130	101,031
Valuation allowance	(76,130)	(101,031)	$ (101,217)	$ (84,319)
Net deferred tax assets	$ 0	$ 0