Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Investment income from portfolios
Total investment income	$ 8,618	$ 8,767
Less: investment expenses	249	250
Investment income, net of expenses	8,369	8,517
Available-for-sale securities
Investment income from portfolios
Total investment income	5,788	6,161
Equity securities
Investment income from portfolios
Total investment income	856	141
Cash equivalents and other
Investment income from portfolios
Total investment income	$ 1,974	$ 2,465

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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