INCOME TAXES - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 2.6	$ 21.3
Income tax expense, percentage of pre-tax income	0.90%	10.50%
Effective tax rate	21.00%	35.00%
Provisional income tax expense			$ 317.8
Provisional estimate of minimum tax on foreign earnings	$ 9.1
Total gross unrecognized tax benefits	69.6		$ 65.4
Net decrease of unrecognized tax benefits	$ (4.2)

Tax Cuts and Jobs Act of 2017, Transition Tax for Accumulated Foreign Earnings,Income Tax Expense (Benefit)

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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