CONTRACT ASSETS AND CONTRACT LIABILITIES - Contract with Customer, Asset and Liability (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Contract Assets
Balance at beginning of year	$ 623.4	$ 345.6
Acquisitions	4.1	237.5
Recognized in current year	849.7	619.3
Reclassified to accounts receivable	(950.4)	(578.6)
Foreign currency impact	17.4	(0.4)
Balance at end of year	544.2	623.4
Contract Liabilities
Balance at beginning of year	799.7	444.8
Acquisitions	6.9	333.9
Recognized in current year	871.9	917.5
Amounts in beginning balance reclassified to revenue	(532.4)	(410.6)
Current year amounts reclassified to revenue	(325.7)	(483.5)
Foreign currency impact	10.8	(2.4)
Balance at end of year	$ 831.2	$ 799.7