DEBT - Deferred Issuance Costs and Write-offs (Details) - USD ($)	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Writeoff of deferred financing fees	$ 21,100,000		$ 3,800,000
Writeoff of original debt discount	3,100,000
Deferred debt issuance cost and debt discount write-off	24,200,000	$ 0	3,800,000
Line of Credit
Debt Instrument [Line Items]
Recognized deferred financing fees	25,400,000	13,400,000	5,900,000
Payments of debt issuance costs	$ 0	$ 800,000	$ 800,000