Income Taxes (Reconciliation of U.S. Federal Statutory Rate To Effective Tax Rate) (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Provision for taxes at U.S. statutory rate	$ 705.9	$ 668.4	$ 631.2
Provision for taxes at U.S. statutory rate, percent	21.00%	21.00%	21.00%
State taxes, net of federal tax benefit	$ 67.2	$ 85.6	$ 80.7
State taxes, net of federal tax benefit, percent	2.00%	2.70%	2.70%
Valuation allowance release on foreign tax credits	$ 0.0	$ (20.3)	$ 0.0
Valuation allowance release on foreign tax credits, percent	0.00%	(0.60%)	0.00%
Foreign rate differential	$ 34.0	$ 44.9	$ 46.9
Foreign rate differential, percent	1.00%	1.40%	1.60%
Excess tax benefit - Stock-based compensation	$ (8.8)	$ (26.9)	$ (29.8)
Excess tax benefit - Stock-based compensation, percent	(0.20%)	(0.80%)	(1.00%)
Other	$ (35.6)	$ (35.6)	$ (16.2)
Other, percent	(1.10%)	(1.20%)	(0.60%)
Total provision for income taxes	$ 762.7	$ 716.1	$ 712.8
Provision for income taxes from continuing operations, percent	22.70%	22.50%	23.70%

Effective Income Tax Rate Reconciliation, Valuation Allowance Release on Foreign Tax Credits, Amount

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Effective Income Tax Rate Reconciliation, Valuation Allowance Release on Foreign Tax Credits, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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