Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Investment income from portfolios
Total investment income	$ 8,289	$ 7,431	$ 17,056	$ 14,691
Less: investment expenses	259	327	509	767
Investment income, net of expenses	8,030	7,104	16,547	13,924
Fixed maturities
Investment income from portfolios
Total investment income	5,488	6,263	11,649	12,373
Equity securities
Investment income from portfolios
Total investment income	141	142	282	284
Cash equivalents and other
Investment income from portfolios
Total investment income	$ 2,660	1,026	$ 5,125	2,034
Erie Family Life Insurance Company
Investment income from portfolios
Note receivable from EFL, interest income recognized by Indemnity		$ 400		$ 800

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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