Long-term Debt (Details) - USD ($)	9 Months Ended
Mar. 31, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Aggregate principal amount	$ 2,000,000,000.0
Notes payable	2,008,700,000	$ 2,010,900,000
Less: current portion	(1,001,800,000)	(2,500,000)
Less: unamortized discount and debt issuance costs	(4,100,000)	(6,200,000)
Total long-term debt	1,002,800,000	2,002,200,000
Fair value of notes issued	2,070,000,000.0
Derivative, notional amount	$ 400,000,000.0
Fixed-rate 2.250% notes due September 15, 2020
Debt Instrument [Line Items]
Debt instrument, term	5 years
Debt instrument effective rate (percent)	2.37%
Notes payable	$ 1,000,000,000.0	1,000,000,000.0
Stated interest rate	2.25%
Fixed-rate 3.375% notes due September 15, 2025
Debt Instrument [Line Items]
Debt instrument, term	10 years
Debt instrument effective rate (percent)	3.47%
Notes payable	$ 1,000,000,000.0	1,000,000,000.0
Stated interest rate	3.375%
Other
Debt Instrument [Line Items]
Notes payable	$ 8,700,000	$ 10,900,000

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Nominal or face amount used to calculate payment on derivative.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt classified as other, payable after one year or the operating cycle, if longer.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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