Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Investment income from portfolios
Total investment income	$ 8,801	$ 7,930	$ 25,857	$ 22,621
Less: investment expenses	149	271	658	1,038
Investment income, net of expenses	8,652	7,659	25,199	21,583
Fixed maturities
Investment income from portfolios
Total investment income	5,449	6,243	17,098	18,616
Equity securities
Investment income from portfolios
Total investment income	452	203	734	487
Cash equivalents and other
Investment income from portfolios
Total investment income	$ 2,900	1,484	$ 8,025	3,518
Erie Family Life Insurance Company
Investment income from portfolios
Note receivable from EFL, interest income recognized by Indemnity		$ 400		$ 1,300

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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