Pension and Other Postretirement Benefits - Components of Net Periodic Other Postretirement Benefit Cost (Details) - Other postretirement benefit plans [Member] - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Net periodic other postretirement benefit costs
Interest cost	$ 107	$ 104
Amortization of prior service credit	(63)	(68)
Recognition of actuarial loss	34	48
Net periodic other postretirement benefit cost	$ 78	$ 84