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LONG-TERM DEBT - Schedule of Long-Term Debt (Details) - USD ($)	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Total principal payments due	$ 4,225,000,000	$ 4,227,500,000
Debt issuance costs	(36,664,000)	(37,945,000)
Total amount outstanding	4,192,923,000	4,194,311,000
Less:
Current portion of long-term debt	610,000,000	610,000,000
Non-current portion of long-term debt	3,582,923,000	3,584,311,000
Senior Notes 2026
Debt Instrument [Line Items]
Premium on notes	4,587,000	4,756,000
Term Loan B
Debt Instrument [Line Items]
Total principal payments due	975,000,000	977,500,000
Less:
Current portion of long-term debt	10,000,000	10,000,000
Senior Notes \| Senior Notes 2030
Debt Instrument [Line Items]
Total principal payments due	900,000,000	900,000,000
Senior Notes \| Senior Notes 2028
Debt Instrument [Line Items]
Total principal payments due	900,000,000	900,000,000
Senior Notes \| Senior Notes 2026
Debt Instrument [Line Items]
Total principal payments due	850,000,000	850,000,000
Revolver \| Line of Credit
Debt Instrument [Line Items]
Total principal payments due	600,000,000	600,000,000	$ 0
Less:
Current portion of long-term debt	$ 600,000,000	$ 600,000,000