SUBSEQUENT EVENTS - Narrative (Details) - USD ($)		1 Months Ended
	Oct. 01, 2021	Oct. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Subsequent Event [Line Items]
Original issue discount			$ 8,731,000	$ 13,355,000
Senior Notes | First lien term loan
Subsequent Event [Line Items]
Original issue discount			$ 8,731,000	$ 7,253,000
Subsequent Event
Subsequent Event [Line Items]
Repayments of long-term debt		$ 69,900,000
Subsequent Event | Senior Notes
Subsequent Event [Line Items]
Third party fees		9,400,000
Original issue discount		1,500,000
Subsequent Event | Senior Notes | First lien term loan
Subsequent Event [Line Items]
Debt instrument, face amount		1,157,000,000
Subsequent Event | Senior Notes | First lien term loan | Interest Rate Cap | Designated as Hedging Instrument
Subsequent Event [Line Items]
Notional amount of derivative		$ 300,000,000
Derivative, term of contract		5 years
Subsequent Event | Senior Notes | New First Lien Term Loan | First Lien Term Loan
Subsequent Event [Line Items]
Debt instrument, face amount		$ 600,000,000
Subsequent Event | Senior Notes | New Senior Unsecured Notes
Subsequent Event [Line Items]
Debt instrument, face amount		$ 500,000,000
Subsequent Event | Infinity Infusion Nursing, LLC
Subsequent Event [Line Items]
Business combination purchase price	$ 50,000,000