SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (REINSURANCE) (NARRATIVE) (Details) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2013 USD ($) subsidiary	Jun. 30, 2014 USD ($)	Dec. 31, 2016 USD ($) subsidiary	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2016 USD ($)
Accounting Policies [Abstract]
Company retains no more than this amount of mortality risk			$ 0.8
Ceded premiums written			123.9	$ 133.6	$ 176.7
Reinsurance benefits netted against insurance policy benefits			130.1	167.7	195.3
Assumed premiums written			$ 34.0	$ 38.5	$ 35.0
Number of insurance subsidiaries | subsidiary	2		3
Percent of coinsurance agreements	100.00%
Ceded long-term reserves	$ 495.0
Additional premiums paid by subsidiaries to enter into coinsurance agreement	$ 96.9
Over-collateralization rate of market-value trusts	7.00%
Discontinued Operation, Income (Loss) from Discontinued Operation Disclosures [Abstract]
Market value of investments						$ 504.7
Insurance liabilities						(552.2)
Write-off of reinsurance receivables						(17.9)
Estimated transaction expenses						(10.0)
Pre-tax loss						(75.4)
Tax benefit						26.4
Increase in valuation allowance for deferred tax assets						(4.1)
After-tax loss						$ (53.1)
Gain related to other reinsurance transactions		$ 3.8