PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount				$ 993.5
Rollforward of common shares issued
Commons Stock Issued During Period Shares Employee Stock Plans		1.0
Stock Repurchased and Retired During Period, Shares		0.9
Stock Repurchased During Period, Shares	0.9
Rollforward of Share Repurchase Program
Outstanding common stock repurchase authorization, beginning balance		$ 401.4
Purchase of common stock		(150.0)	$ (256.0)
Outstanding common stock repurchase authorization, ending balance	$ 1,000.0	$ 1,000.0
Common Shares Outstanding Rollforward [Abstract]
Common shares outstanding, beginning balance (in shares)		101.9
Commons Stock Issued During Period Shares Employee Stock Plans		1.0
Stock Repurchased and Retired During Period, Shares		0.9
Restricted Stock Awards And Performance Shares Surrendered		$ 45.1	46.2
Common shares outstanding, ending balance (in shares)	102.0	102.0
Commons Stock Issued During Period Shares Employee Stock Plans		1.0
Rollforward of common shares held in treasury
Treasury Stock, Carrying Basis				$ 150.0
Common Stock, Shares Authorized				265.0
Common Stock, Par or Stated Value Per Share				$ 0.10
Preferred Stock, Shares Authorized				30.0
Preferred Stock, Par or Stated Value Per Share				$ 0.10
Stock Repurchased and Retired During Period, Shares		0.9
Restricted Stock Awards And Performance Shares Surrendered		$ 45.1	$ 46.2
Preferred Stock, Shares Outstanding				0.0
Common Stock [Member]
Rollforward of common shares issued
Common shares issued, beginning balance (in shares)		125.1
Commons Stock Issued During Period Shares Employee Stock Plans		1.0
Stock Repurchased and Retired During Period, Shares		0.9
Common shares issued, ending balance (in shares)	125.2	125.2
Common Stock, Shares, Issued	125.2	125.1		125.2
Common Shares Outstanding Rollforward [Abstract]
Commons Stock Issued During Period Shares Employee Stock Plans		1.0
Stock Repurchased and Retired During Period, Shares		0.9
Commons Stock Issued During Period Shares Employee Stock Plans		1.0
Rollforward of common shares held in treasury
Stock Repurchased and Retired During Period, Shares		0.9
Treasury Stock, Common [Member]
Rollforward of common shares issued
Commons Stock Issued During Period Shares Employee Stock Plans		0.0
Stock Repurchased and Retired During Period, Shares		0.0
Common Shares Outstanding Rollforward [Abstract]
Commons Stock Issued During Period Shares Employee Stock Plans		0.0
Stock Repurchased and Retired During Period, Shares		0.0
Commons Stock Issued During Period Shares Employee Stock Plans		0.0
Rollforward of common shares held in treasury
Common shares held in Treasury, beginning balance (in shares)		(23.2)
Common shares held in Treasury, ending balance (in shares)	(23.2)	(23.2)
Treasury Stock, Shares	23.2	23.2		23.2
Stock Repurchased and Retired During Period, Shares		0.0