OUT-OF-PERIOD ADJUSTMENTS (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Decrease on insurance policy benefits	$ (634.2)	$ (632.4)	$ (1,303.5)	$ (1,251.4)
Increase on tax expense	45.1	22.8	79.5	17.8
Increase on net income	83.4	$ 59.9	$ 145.7	$ 105.4
Restatement Adjustment \| Bankers Life \| Long-term Care Insurance Benefits
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Decrease on insurance policy benefits	1.7
Increase on tax expense	(0.6)
Increase on net income	$ 1.1
Adjustment to net income per diluted share (in dollars per share)	$ 0.01

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

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