Variable Interest Entities (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)
Subsidiary - HG Global
Variable Interest Entity [Line Items]
Purchase of surplus notes	$ 503.0
Subsidiary - HG Global \| Maximum
Variable Interest Entity [Line Items]
Percentage of par value of policy reinsured	15.00%
Subsidiary - BAM
Variable Interest Entity [Line Items]
BAM member surplus contributions	$ 545.2
Variable Interest Entity, Not Primary Beneficiary \| PassportCard/DavidShield
Variable Interest Entity [Line Items]
Ownership interest	53.80%
Partnership interest, carrying value	$ 159.6
Variable Interest Entity, Not Primary Beneficiary \| Elementum Holdings, L.P.
Variable Interest Entity [Line Items]
Ownership interest	26.60%
Partnership interest, carrying value	$ 35.0
Variable Interest Entity, Not Primary Beneficiary \| Limited Partnerships
Variable Interest Entity [Line Items]
Partnership interest, carrying value	$ 248.6

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Percentage of par value of policy reinsured.

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