BUSINESS COMBINATIONS - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Transaction, integration and restructuring	$ (65.9)	$ 330.8	$ 620.3
OppenheimerFunds
Business Acquisition [Line Items]
Transaction, integration and restructuring	$ 190.7	$ 183.2