INCOME TAXES - NARRATIVE (Details) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2016 USD ($)	Mar. 31, 2016 USD ($) adjustment	Mar. 31, 2015 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2015 USD ($)
Operating Loss Carryforwards [Line Items]
Deferred tax assets more likely than not to be realized through future taxable earnings		$ 879.6			$ 946.6
Net deferred tax assets		1,073.1			1,160.1
Valuation allowance		193.5			213.5
Change in valuation allowance		$ 20.0	$ 0.0
Assumed period adjusted annual taxable income will remain flat		2 years
Deferred tax valuation analysis, growth rate for the next five years		3.00%
Valuation allowance model, forecast period of Model		5 years
Estimated normalized annual taxable income for the current year		$ 345.0
Adjusted average non-life taxable income		85.0
Adjusted average life taxable income		$ 260.0
Loss limitation based on income of life insurance company, percent		35.00%
Loss limitation based on loss of non-life entities, percent		35.00%
Federal long-term tax exempt rate		2.65%
Ownership change threshold restricting NOL usage		50.00%
Capital loss carryforwards		$ 34.9
Net state operating loss carryforwards		13.9			$ 14.1
Loss on investment in senior health				$ 878.0
Capital loss carryforwards that would have expired if IRS position is determined to be correct		473.0
Unrecognized tax benefit related to loss on investment in Senior Health		166.0
Increase in valuation allowance if unrecognized tax benefit is recognized		$ 34.0
Number Of Adjustments Proposed As A Result Of Internal Revenue Service Examination | adjustment		2
Future cash tax payments based on income of life insurance company, percent		65.00%
TCP [Member] | Subsequent Event [Member]
Operating Loss Carryforwards [Line Items]
Additional investments to be made over time	$ 250.0
Capital Loss Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance		$ 7.0
Federal [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance		176.5
Net operating loss carryforwards		2,500.0
State [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance		10.0
Life insurance companies [Member]
Operating Loss Carryforwards [Line Items]
Increase (decrease) in estimated normalized annual taxable income		(10.0)
Net operating loss carryforwards		449.4
Loss on investment in senior health				742.0
Non life insurance companies [Member]
Operating Loss Carryforwards [Line Items]
Increase (decrease) in estimated normalized annual taxable income		10.0
Net operating loss carryforwards		$ 2,614.9
Loss on investment in senior health				$ 136.0