Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 84,276	$ 97,707
Less: investment expenses	(4,695)	(4,457)
Net investment income	79,581	93,250
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	102	221
Commercial mortgage and other loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	13,776	12,491
Policy loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	17,311	16,199
Short-term investments and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	2,032	2,311
Other invested assets
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	(3,909)	9,911
Available-for-sale \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	54,566	56,266
Trading \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 398	$ 308

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.

+ References

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