COMPREHENSIVE INCOME (LOSS) - SUMMARY OF COMPREHENSIVE INCOME, NET OF TAX (Details) - Foreign Currency Translation Gain (Loss) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Condensed Statement of Income Captions [Line Items]
Foreign currency translation gains (losses)	$ (123.0)	$ (71.9)
Net Investment Hedging
Condensed Statement of Income Captions [Line Items]
Foreign currency translation gains (losses)	$ 4.3	$ 10.6

Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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