Income Taxes (Components of Deferred Income Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Jun. 30, 2021
Deferred tax assets:
Accrued expenses not currently deductible	$ 212.1	$ 244.2
Stock-based compensation expense	43.5	38.4
Foreign tax credits	5.9	21.3
Net operating losses	34.1	46.3
Prepaid royalty	33.7	0.0
Unrealized investment losses, net	407.2	0.0
Other	38.3	34.7
Deferred tax assets, gross	774.8	384.9
Less: valuation allowances	(18.9)	(13.4)
Deferred tax assets, net	755.9	371.5
Deferred tax liabilities:
Deferred revenue	529.9	494.5
Fixed and intangible assets	6.5	119.4
Prepaid expenses	94.8	27.9
Prepaid retirement benefits	4.6	37.7
Unrealized investment gains, net	0.0	101.7
Tax on unrepatriated earnings	11.5	11.4
Other	18.2	13.6
Deferred tax liabilities	665.5	806.2
Net deferred tax (assets)/liabilities		$ 434.7
Net deferred tax (assets)/liabilities	$ (90.4)