INCOME TAXES - Expirations of Tax Loss Carry Forwards (Details) $ in Millions	Jun. 30, 2019 USD ($)
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	$ 1,272.7
Tax Year 2020
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	68.1
Tax Year 2021
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	13.3
Tax Year 2022
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	19.7
Tax Year 2023
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	10.0
Tax Year 2024 and Thereafter
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	1,161.6
United States
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	149.8
United States | Tax Year 2020
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	0.0
United States | Tax Year 2021
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	0.0
United States | Tax Year 2022
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	0.0
United States | Tax Year 2023
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	0.0
United States | Tax Year 2024 and Thereafter
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	149.8
Western Europe
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	838.3
Western Europe | Tax Year 2020
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	0.0
Western Europe | Tax Year 2021
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	0.0
Western Europe | Tax Year 2022
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	1.2
Western Europe | Tax Year 2023
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	1.7
Western Europe | Tax Year 2024 and Thereafter
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	835.4
Rest of World
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	284.6
Rest of World | Tax Year 2020
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	68.1
Rest of World | Tax Year 2021
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	13.3
Rest of World | Tax Year 2022
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	18.5
Rest of World | Tax Year 2023
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	8.3
Rest of World | Tax Year 2024 and Thereafter
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	$ 176.4