DERIVATIVES - FAIR VALUE BY BALANCE SHEET LOCATION (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fixed indexed call options
Derivatives, Fair Value [Line Items]
Fixed indexed call options	$ 195.2	$ 323.5
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total assets	179.5	308.2
Not Designated as Hedging Instrument \| Fixed indexed call options \| Other invested assets
Derivatives, Fair Value [Line Items]
Fixed indexed call options	195.2	323.5
Not Designated as Hedging Instrument \| Reinsurance receivables \| Reinsurance receivables
Derivatives, Fair Value [Line Items]
Reinsurance receivables	(15.7)	(15.3)
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	$ 1,564.2	$ 1,600.6

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

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