Concentrations of Credit Risk (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Concentration Risk [Line Items]
Receivables from Erie Insurance Exchange and affiliates, net	$ 503,413	$ 494,637
Erie Insurance Exchange
Concentration Risk [Line Items]
Current expected credit loss allowance	$ 600	$ 600

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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