Employee Benefit Plans - Severance Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Retirement Benefits [Abstract]
Service cost	$ 496	$ 489	$ 506
Interest cost	46	66	89
Amortization of actuarial (gain) loss	(427)	(338)	(404)
Net periodic benefit cost — Total cost	$ 115	$ 217	$ 191