Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Provision for income taxes	20.70%	19.20%
Valuation allowance	$ 0	$ 0	$ 0
Gross deferred tax asset related to unrealized losses on fixed-maturity securities	482,500,000	582,600,000	427,300,000
Accrued income taxes	$ 961,800,000	$ 203,300,000	$ 311,800,000

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due. This amount is the total of current and noncurrent accrued income taxes.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from unrealized loss on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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