INCOME TAXES QTR (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
INCOME TAXES
Statutory federal income tax rate (as a percent)			21.00%		35.00%
Net tax charge	$ (1.9)		$ (5.4)		$ 24.8
Recognized charge representing provisional estimate of one-time transition tax	0.9		(2.6)		31.6
Estimate of deferred income tax benefit related to corporate rate change	$ (2.8)		$ (2.8)		(6.8)
Effective income tax rate (as a percent)	23.40%	23.00%	25.60%	22.00%
Tax benefits from employee share-based compensation	$ (4.5)		$ (9.9)	$ (8.8)
Refunds from settlement of tax claims	(3.5)	$ (4.4)	(3.9)	(3.4)
Additional foreign valuation allowance	1.4
Impact of new tax provisions, including GILTI and BEAT	1.5		6.3
Impact of other discrete and non-discrete tax items	4.0		4.5
Benefit from repatriation activities to the U.S.				$ 3.6
Income tax uncertainties	3.5		3.5		3.1
Amount of income tax uncertainties that, if recognized, would impact the effective tax rate	3.5		3.5		$ 3.1
Decrease in liability for uncertain tax positions, high end of range	$ 1.5		$ 1.5

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