Concentrations of Credit Risk (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Receivables from Erie Insurance Exchange and its affiliates	$ 482,238,000		$ 468,636,000
Erie Insurance Exchange
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in allowance for credit loss	$ 0
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		$ 600,000