Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020
Summary Of Significant Accounting Policies [Line Items]
Allowance for doubtful accounts receivable	$ 3.2	$ 3.1
Amount of tax expense (benefit) for changes in the fair value of interest rate swap agreements	11.8	4.5	$ (8.7)
Accumulated other comprehensive loss related to foreign currency translation adjustments	(45.3)	(15.9)	(38.6)
Accumulated other comprehensive income (loss) related to fair value of interest rate swaps	13.1	(20.5)	(33.2)
Accumulated other comprehensive income (loss) related to unrecognized post-retirement plan costs	$ 1.1	$ 0.1	$ (0.5)
Equipment and furniture
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	from three to eight years
Leasehold improvements
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	over the remaining lease term or the useful life of the improvements, whichever is shorter