Pension and Post-retirement Benefits - Net Periodic Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0
Interest cost	1,033	1,113
Expected return on plan assets	(1,100)	(1,108)
Amortization of net loss	14	13
Total	(53)	18
Post Retirement Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	9	21
Interest cost	12	51
Amortization of prior service credit	(368)	(134)
Amortization of net loss	47	42
Total	$ (300)	$ (20)