ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME, NET (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024
AOCI Rollforward
Beginning balance	$ 4,021.7	$ 4,024.1	$ 3,985.0	$ 3,664.4	$ 3,538.7	$ 3,465.3	$ 3,985.0
Other comprehensive income	44.2	(3.2)	(13.8)	(49.0)	9.8	18.8
Ending balance	4,208.3	4,021.7	4,024.1	3,788.3	3,664.4	3,538.7	4,208.3
Foreign Currency Translation Adjustment
AOCI Rollforward
Beginning balance			(5.6)				(5.6)
Other comprehensive income							23.4
Ending balance	17.8						17.8
Available-for-sale Financial Investments
AOCI Rollforward
Beginning balance			(3.7)				(3.7)
Other comprehensive income							3.7
Ending balance	0.0						0.0
Post-Retirement Benefits
AOCI Rollforward
Beginning balance			(0.1)				(0.1)
Other comprehensive income							0.1
Ending balance	0.0						0.0
Accumulated other comprehensive (loss) income, net
AOCI Rollforward
Beginning balance	(26.4)	(23.2)	(9.4)	(2.4)	(12.2)	(31.0)	(9.4)
Other comprehensive income	44.2	(3.2)	(13.8)	(49.0)	9.8	18.8	27.2
Ending balance	$ 17.8	$ (26.4)	$ (23.2)	$ (51.4)	$ (2.4)	$ (12.2)	$ 17.8