OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other comprehensive income/(loss), net of tax:
Currency translation differences on investments in foreign subsidiaries	$ 144.9	$ (463.1)	$ (73.4)
Other comprehensive income/(loss), net	(4.3)	(37.8)	36.4
Other comprehensive income/(loss)	140.6	(500.9)	(37.0)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	15,843.5	16,168.0	14,808.9
Other comprehensive income/(loss), net of tax	140.6	(500.9)	(37.0)
Ending balance	15,170.3	15,843.5	16,168.0
Accumulated Other Comprehensive Income/(Loss)
Other comprehensive income/(loss), net of tax:
Other comprehensive income/(loss)	140.6	(500.9)	(37.0)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(942.4)	(441.5)	(404.5)
Other comprehensive income/(loss), net of tax	140.6	(500.9)	(37.0)
Ending balance	(801.8)	(942.4)	(441.5)
Foreign currency translation
Other comprehensive income/(loss), net of tax:
Currency translation differences on investments in foreign subsidiaries	144.9	(463.1)	(73.4)
Other comprehensive income/(loss), net	0.0	0.0	0.0
Other comprehensive income/(loss)	144.9	(463.1)	(73.4)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(815.0)	(351.9)	(278.5)
Other comprehensive income/(loss), net of tax	144.9	(463.1)	(73.4)
Ending balance	(670.1)	(815.0)	(351.9)
Employee benefit plans
Other comprehensive income/(loss), net of tax:
Currency translation differences on investments in foreign subsidiaries	0.0	0.0	0.0
Other comprehensive income/(loss), net	(4.3)	(37.8)	36.4
Other comprehensive income/(loss)	(4.3)	(37.8)	36.4
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(127.4)	(89.6)	(126.0)
Other comprehensive income/(loss), net of tax	(4.3)	(37.8)	36.4
Ending balance	$ (131.7)	$ (127.4)	$ (89.6)