Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Deferred tax assets:
Federal, state, and foreign net operating loss carryovers	$ 501	$ 448
Stock option compensation	824	1,262
Accrued vacation, allowance for returns, bonuses & other	2,067	2,672
Gross deferred tax asset	3,392	4,382
Deferred tax liabilities:
Patents and trademarks	(117)	(132)
Property & equipment	(801)	(1,194)
Other	(59)	(104)
Gross deferred tax liabilities	(977)	(1,430)
Less: valuation allowance	(251)	(259)
Deferred tax assets, net	$ 2,164	$ 2,693