PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Class of Stock [Line Items]
Treasury Stock, Shares, Retired				0.0
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased						1,050.0
Stock Repurchase Program, Authorized Amount						$ 1,250.0
Rollforward of common shares issued
Commons Stock Issued During Period Shares Employee Stock Plans				1.0
Stock Repurchased and Retired During Period, Shares				(2.0)
Stock Repurchased During Period, Shares	0.8	1.3
Treasury Stock Acquired, Average Cost Per Share				$ 131.71
Payments for Repurchase of Common Stock	$ 199.9			$ 300.0	$ 150.0
Rollforward of Share Repurchase Program
Outstanding common stock repurchase authorization, beginning balance		$ 443.5		$ 443.5
Purchase of common stock		$ (100.1)	$ (75.0)
Common Shares Outstanding Rollforward [Abstract]
Common shares outstanding, beginning balance (in shares)		98.9		98.9
Commons Stock Issued During Period Shares Employee Stock Plans				1.0
Stock Repurchased and Retired During Period, Shares				(2.0)
Common shares outstanding, ending balance (in shares)	97.8			97.8
Commons Stock Issued During Period Shares Employee Stock Plans				1.0
Rollforward of common shares held in treasury
Treasury Stock, Carrying Basis						$ 100.1
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				(2.0)
Preferred Stock, Shares Outstanding						0.0
Restricted Stock Awards And Performance Shares Surrendered, share amount				(0.1)
Common Stock [Member]
Class of Stock [Line Items]
Treasury Stock, Shares, Retired				(23.6)
Rollforward of common shares issued
Common shares issued, beginning balance (in shares)		122.4		122.4
Commons Stock Issued During Period Shares Employee Stock Plans				1.0
Stock Repurchased and Retired During Period, Shares				(2.0)
Common shares issued, ending balance (in shares)	97.8			97.8
Common Stock, Shares, Issued	97.8	122.4		122.4		97.8
Common Shares Outstanding Rollforward [Abstract]
Commons Stock Issued During Period Shares Employee Stock Plans				1.0
Stock Repurchased and Retired During Period, Shares				(2.0)
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				(2.0)
Restricted Stock Awards And Performance Shares Surrendered, share amount				0.0
Treasury Stock, Common [Member]
Class of Stock [Line Items]
Treasury Stock, Shares, Retired				(23.6)
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)		(23.5)		(23.5)
Common shares held in Treasury, ending balance (in shares)	0.0			0.0
Treasury Stock, Shares	0.0	23.5		23.5		0.0
Stock Repurchased and Retired During Period, Shares				0.0
Restricted Stock Awards And Performance Shares Surrendered, share amount				(0.1)