DERIVATIVES - FAIR VALUE BY BALANCE SHEET LOCATION (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fixed indexed call options
Derivatives, Fair Value [Line Items]
Fixed indexed call options	$ 294.2	$ 323.5
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total assets	278.3	308.2
Not Designated as Hedging Instrument \| Fixed indexed call options \| Balance Sheet Location [Axis]: us-gaap:OtherInvestments
Derivatives, Fair Value [Line Items]
Fixed indexed call options	294.2	323.5
Not Designated as Hedging Instrument \| Reinsurance receivables \| Balance Sheet Location [Axis]: us-gaap:ReinsuranceRecoverablesOnPaidLosses
Derivatives, Fair Value [Line Items]
Reinsurance receivables	(15.9)	(15.3)
Not Designated as Hedging Instrument \| Embedded derivatives related to fixed indexed annuities at fair value \| Balance Sheet Location [Axis]: us-gaap:PolicyholderFunds
Derivatives, Fair Value [Line Items]
Policyholder account balances	$ 1,676.7	$ 1,600.6

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

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