Income Taxes - Unrecognized Roll Forward (Details) - USD ($)	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Reconciliation of unrecognized tax benefits:
Balance of gross unrecognized tax benefits as of Beginning of Year	$ 678,000	$ 678,000	$ 866,000
Increase (Decrease) to unrecognized tax benefits from deemed dividends for investments in US property	0	0	(3,000)
Increase (Decrease) to unrecognized tax benefits resulting from the release of R&D credits due to the settled IRS audit	0	0	(185,000)
Increase (Decrease) to unrecognized tax benefits resulting from a state filing tax position	22,000	0	0
Balance of gross unrecognized tax benefits as of End of Year	$ 700,000	$ 678,000	$ 678,000