Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 765,166	$ 532,063
Less: investment expenses	(30,370)	(26,743)
Net investment income	734,796	505,320
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	18,584	3,747
Commercial mortgage and other loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	97,247	73,758
Policy loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	16,216	14,445
Other invested assets
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	63,879	23,320
Short-term investments and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	34,837	46,315
Available-for-sale \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	487,200	338,809
Trading \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 47,203	$ 31,669

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