ACCOUNTING FOR DERIVATIVES - FAIR VALUE BY BALANCE SHEET LOCATION (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fixed indexed call options
Derivatives, Fair Value [Line Items]
Fixed indexed call options	$ 150.0	$ 56.7
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total assets	129.7	38.9
Total liabilities	1,213.4	1,297.0
Not Designated as Hedging Instrument \| Fixed indexed call options \| Other invested assets
Derivatives, Fair Value [Line Items]
Fixed indexed call options	150.0	56.7
Not Designated as Hedging Instrument \| Reinsurance receivables \| Reinsurance receivables
Derivatives, Fair Value [Line Items]
Reinsurance receivables	(20.3)	(17.8)
Not Designated as Hedging Instrument \| Embedded derivatives related to fixed indexed annuities at fair value \| Policyholder account balances
Derivatives, Fair Value [Line Items]
Total liabilities	1,676.1	1,788.4
Not Designated as Hedging Instrument \| Embedded derivatives related to fixed indexed annuities at fair value \| Future policy benefits
Derivatives, Fair Value [Line Items]
Total liabilities	$ (462.7)	$ (491.4)

Derivative Asset, Not Subject to Master Netting Arrangements

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Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangements

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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