ACCOUNTING FOR DERIVATIVES - SCHEDULE PRE-TAX GAINS (LOSSES) RECOGNIZED IN NET INCOME FOR DERIVATIVE INSTRUMENTS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 23.8	$ 18.8	$ 3.6	$ 3.9
Investment Income [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(5.9)	31.5	(8.0)	35.3
Investment Income [Member] | Equity Swap [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(5.9)	31.3	(8.0)	36.7
Investment Income [Member] | Embedded Derivative Financial Instruments [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	0.0	0.2	0.0	(1.4)
Gain (Loss) on Investments [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(5.6)	(1.9)	(5.9)	(4.6)
Gain (Loss) on Investments [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	0.1	(1.9)	(1.6)	(4.6)
Insurance Policy Benefits [Member] | Embedded Derivative Financial Instruments [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	35.3	(10.8)	17.5	(26.8)
Coinsurance [Member] | Gain (Loss) on Investments [Member] | Embedded Derivative Financial Instruments [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (5.7)	$ 0.0	$ (4.3)	$ 0.0