INCOME TAXES - Changes in Balance of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit - beginning of year	$ 5.3	$ 5.6	$ 13.9
Gross increases - tax positions in prior period	15.9	1.2	0.0
Gross decreases - tax positions in prior period	(0.8)	(0.4)	(2.3)
Gross increases - tax positions in current period	0.0	0.2	0.4
Settlements	0.0	0.0	0.0
Lapse of statute of limitations	(1.7)	(1.3)	(6.4)
Change due to foreign currency exchange rates	0.0	0.0	0.0
Unrecognized tax benefit - end of year	$ 18.7	$ 5.3	$ 5.6

Unrecognized Tax Benefits, Increase (Decrease) Resulting From Foreign Currency Translation

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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- Definition

Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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