INVESTMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investments in and Advances to Affiliates [Abstract]
Equity method investments gains	$ 18.9	$ 8.9	$ 99.3	$ 1.8

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration