Employee Benefit Plans - Severance Plans - Components and Changes of Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Changes and Components of Benefit Obligation:
Benefit obligation at beginning of year	$ 2,739	$ 2,784
Service cost	496	489	$ 506
Interest cost	46	66	89
Actuarial (gain) loss for the period	(258)	(596)
Benefits paid	(52)	(4)
Benefit obligation at end of year	2,971	2,739	$ 2,784
Balance in current liabilities	540	498
Balance in non-current liabilities	2,431	2,241
Total benefit obligation recognized in the Consolidated Balance Sheets	$ 2,971	$ 2,739