DERIVATIVES - FAIR VALUE BY BALANCE SHEET LOCATION (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Fixed indexed call options
Derivatives, Fair Value [Line Items]
Fixed indexed call options	$ 210.4	$ 279.0
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total assets	194.6	261.9
Not Designated as Hedging Instrument \| Fixed indexed call options \| Other invested assets
Derivatives, Fair Value [Line Items]
Fixed indexed call options	210.4	279.0
Not Designated as Hedging Instrument \| Reinsurance receivables \| Reinsurance receivables
Derivatives, Fair Value [Line Items]
Reinsurance receivables	(15.8)	(17.1)
Not Designated as Hedging Instrument \| Embedded derivatives related to fixed indexed annuities at fair value \| Policyholder account balances
Derivatives, Fair Value [Line Items]
Policyholder account balances	$ 1,502.4	$ 1,471.6

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

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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