EARNINGS PER SHARE - Schedule of Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Basic:
Net income	$ 186.1	$ 126.6	$ 416.3	$ 269.6
Weighted-average shares outstanding (in shares)	210.5	212.2	210.8	212.6
Basic earnings per share (in dollars per share)	$ 0.88	$ 0.60	$ 1.97	$ 1.27
Diluted:
Net income	$ 186.1	$ 126.6	$ 416.3	$ 269.6
Weighted-average shares outstanding (in shares)	210.5	212.2	210.8	212.6
Dilutive effect of stock plans (in shares)	5.2	5.1	5.3	5.0
Dilutive weighted-average shares outstanding	215.7	217.3	216.1	217.6
Diluted earnings per share (in dollars per share)	$ 0.86	$ 0.58	$ 1.93	$ 1.24