Retirement Benefits - Net periodic pension cost recognized (Details) - Pension Plan - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 76,638	$ 84,188	$ 82,743
Interest cost	110,250	102,475	142,479
Expected return on plan assets	(267,888)	(267,579)	(266,674)
Amortization of prior service cost	4,103	5,325	5,633
Amortization of unrecognized actuarial loss	157,288	207,897	165,815
Amortization of transition obligation	8	18	18
Net periodic benefit cost	$ 80,399	$ 132,324	$ 130,014