OTHER CURRENT ASSETS & OTHER CURRENT LIABILITIES - Other Current Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Other Current Assets and Other Current Liabilities [Abstract]
Value - added tax and other taxes payable	$ 193.2	$ 168.8
Value - added tax and other taxes payable	126.2	91.4
Legal provisions	129.6	127.6
BPI Share Purchase Agreement payable	100.0	0.0
Social security liability	65.9	67.9
Taxes Payable, Current	59.0	0.0
Provisions	36.1	53.0
Compensation accrual	18.6	54.3
Current portion of accrued pension and other post-retirement benefits	7.1	6.9
Other accrued liabilities	249.9	230.2
Total other current liabilities	$ 985.6	$ 800.1