Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 189,670	$ 104,252
Less: investment expenses	(10,370)	(5,385)
Net investment income	179,300	98,867
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	162	103
Commercial mortgage and other loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	22,248	13,426
Policy loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	16,944	17,034
Other invested assets
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	24,912	13,073
Short-term investments and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	648	127
Available-for-sale \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	109,191	59,958
Trading \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 15,565	$ 531

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 of expenses related to the generation of investment income.

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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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