Long-term Debt (Detail Textual) - USD ($)	9 Months Ended
Mar. 31, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Outstanding amount under Credit Facility	$ 1,768,204,000	$ 1,073,394,000
Interest Rate Swap \| Cash Flow Hedging
Debt Instrument [Line Items]
Aggregate notional amount	400,000,000
Bank Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 2,438,400,000
Outstanding borrowings interest rate	3.53%
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 1,500,000,000
Outstanding amount under Credit Facility	865,000,000	135,000,000
Term loans
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	938,400,000
Outstanding amount under Credit Facility	$ 903,204,000	$ 938,394,000
Term loan period	5 years
Loan maturity date	Jun. 30, 2023
Term loan frequency of payment	quarterly
Term loans \| Principal Payment Through June 30, 2021
Debt Instrument [Line Items]
Term loan principal payment	$ 11,700,000
Term loans \| Principal Payment Thereafter June 30, 2021
Debt Instrument [Line Items]
Term loan principal payment	23,500,000
Same-Day Swing Line Loan Revolving Credit Subfacility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	100,000,000
Outstanding amount under Credit Facility	0
Stand-By Letters Of Credit Revolving Credit Subfacility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 25,000,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Date the credit facility terminates, in CCYY-MM-DD format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Description of the frequency of periodic payments, which may be presented in a variety of ways (for example, monthly, quarterly, annually).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of the required periodic payment applied to principal.

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