Significant Accounting Policies (Details) - USD ($) $ in Thousands		Mar. 31, 2020	Jan. 01, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Agent loans, allowance for credit loss		$ 1,000
Cumulative effect adjustment	[1]		$ 1,075
Available-for-sale securities, allowance for credit loss		600
Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Agent loans, allowance for credit loss			800
Cumulative effect adjustment			1,100
Available-for-sale securities, allowance for credit loss		$ 600
Erie Insurance Exchange | Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Receivables from Erie Insurance Exchange, allowance for credit loss			$ 600

[1] The cumulative effect adjustment is related to the implementation of new credit loss allowance accounting guidance effective January 1, 2020. See Note 2. "Significant Accounting Policies".