Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 21,646	$ 20,331	$ 39,556	$ 39,930
Less: investment expenses	(963)	(859)	(1,908)	(1,717)
Net investment income	20,683	19,472	37,648	38,213
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	91	91	182	182
Commercial mortgage and other loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	1,442	1,324	2,844	2,501
Policy loans
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	2,885	2,846	5,761	5,580
Other invested assets
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	1,370	1,414	325	3,096
Short-term investments and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	56	322	359	602
Available-for-sale \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	15,681	14,248	29,843	27,806
Trading \| Fixed maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 121	$ 86	$ 242	$ 163

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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