Amount of other deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. For example, but not limited to, acquisition-date income tax benefits or expenses recognized from changes in the acquirer's valuation allowance for its previously existing deferred tax assets resulting from a business combination and adjustments to beginning-of-year balance of a valuation allowance because of a change in circumstance causing a change in judgment about the realizability of the related deferred tax asset in future periods.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Investments, Owned, Federal Income Tax Note [Line Items]
Net deferred tax benefit					$ 68.0
Effective tax rate	(18.70%)	1.10%	8.70%	5.60%
P&C Insurance and Reinsurance (Ark/WM Outrigger) \| Ark
Investments, Owned, Federal Income Tax Note [Line Items]
Net deferred tax benefit					51.0
Financial Guarantee (HG Global/BAM) \| HG Global
Investments, Owned, Federal Income Tax Note [Line Items]
Net deferred tax benefit					$ 17.0