MARKETABLE SECURITIES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Available-for-sale equity securities	$ 19.6		$ 20.0
Unrealized (loss) gain recorded in other income	0.8	$ (4.4)
Losses recorded on securities intended to be sold	3.2	1.5
Unrealized Gains/(Losses) on Marketable Securities
Debt Securities, Available-for-sale [Line Items]
Losses recorded on securities intended to be sold	1.2	$ 0.0
CYAPC and YAEC
Debt Securities, Available-for-sale [Line Items]
Available-for-sale equity securities	170.9		170.1
Marketable securities held in nuclear decommissioning trust	$ 161.2		$ 163.2

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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