Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Provision for income taxes	21.60%	20.70%	21.00%	19.90%
Valuation allowance	$ 0	$ 0	$ 0	$ 0	$ 0
Gross deferred tax asset related to unrealized losses on fixed-maturity securities	453,900,000	703,700,000	453,900,000	703,700,000	427,300,000
Accrued income taxes	$ 9,000,000		$ 9,000,000		$ 311,800,000
Income Taxes Receivable		$ 44,000,000		$ 44,000,000

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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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

+ References

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