GOODWILL AND INTANGIBLE ASSETS - SCHEDULE OF GOODWILL (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Goodwill [Roll Forward]
Beginning balance January 1	$ 3,280.1	$ 3,262.3
Ending balance December 31	3,343.4	3,280.1
Goodwill, Acquired During Period	19.8	151.9
Goodwill, Transfers		(58.1)
Goodwill, Foreign Currency Translation, Gain (Loss)	43.5	(76.0)
EES
Goodwill [Roll Forward]
Beginning balance January 1	799.3	838.1
Ending balance December 31	843.8	799.3
Goodwill, Acquired During Period	20.1	4.7
Goodwill, Transfers		0.0
Goodwill, Foreign Currency Translation, Gain (Loss)	24.4	(43.5)
UBS
Goodwill [Roll Forward]
Beginning balance January 1	1,133.8	1,212.6
Ending balance December 31	1,145.5	1,133.8
Goodwill, Acquired During Period	0.0	0.0
Goodwill, Transfers		(58.1)
Goodwill, Foreign Currency Translation, Gain (Loss)	11.7	(20.7)
CSS
Goodwill [Roll Forward]
Beginning balance January 1	1,347.0	1,211.6
Ending balance December 31	1,354.1	1,347.0
Goodwill, Acquired During Period	(0.3)	147.2
Goodwill, Transfers		0.0
Goodwill, Foreign Currency Translation, Gain (Loss)	$ 7.4	$ (11.8)

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

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