Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 532,063	$ 366,388
Less: investment expenses	(26,743)	(16,938)
Net investment income	505,320	349,450
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	3,747	2,777
Commercial mortgage and other loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	73,758	48,656
Policy loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	14,445	4,996
Other invested assets
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	23,320	26,099
Short-term investments and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	46,315	31,176
Available-for-sale \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	338,809	234,810
Trading \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 31,669	$ 17,874

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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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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