EQUITY - Schedule of Changes in Common Shares and Treasury Stock (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Changes in Common Shares and Treasury Stock [Roll Forward]
Common stock (in shares)	207.2
Common stock (in shares)	191.4	207.2
Treasury stock, beginning value	$ 362.6
Treasury stock, ending value	$ 362.6	$ 362.6
Treasury Stock
Changes in Common Shares and Treasury Stock [Roll Forward]
Treasury stock (in shares)	4.9	4.8	3.5
Stock-based compensation (in shares)	0.0	0.1	0.2
Treasury stock purchases (in shares)	5.6	0.6	1.1
Retirement of treasury stock (in shares)	(5.6)	(0.6)
Accelerated Share Repurchase (in shares)	0.0
Treasury stock (in shares)	4.9	4.9	4.8
Treasury stock, beginning value	$ 362.6	$ 351.9	$ 244.6
Treasury stock reissued at lower than repurchase price	0.0	7.9	18.9
Treasury stock purchases	437.0	52.9	88.4
Retirement of Treasury stock	(437.0)	(50.1)
Accelerated Share Repurchase	0.0
Treasury stock, ending value	$ 362.6	$ 362.6	$ 351.9
Common Stock
Changes in Common Shares and Treasury Stock [Roll Forward]
Common stock (in shares)	207.2	206.8	206.0
Stock-based compensation (in shares)	0.5	1.0	0.8
Treasury stock purchases (in shares)	0.0	0.0	0.0
Retirement of treasury stock (in shares)	(5.6)	(0.6)
Accelerated Share Repurchase (in shares)	(10.7)
Common stock (in shares)	191.4	207.2	206.8
Retirement of Treasury stock	$ (0.2)