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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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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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Equity Capital, Expected Contribution Payments

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Percentage of par value of policy reinsured.

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Variable Interest Entities (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Apr. 30, 2024
Bamboo CRV
Variable Interest Entity [Line Items]
Expected capital contributions	$ 30.0	$ 30.0
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	$ 571.1
PassportCard/DavidShield \| Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Ownership interest	53.80%
Partnership interest, carrying value	$ 158.8
Elementum Holdings, L.P. \| Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Ownership interest	26.60%
Partnership interest, carrying value	$ 35.0
Limited Partnerships \| Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Partnership interest, carrying value	$ 264.0