Related Party (Details) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
	Jan. 31, 2023	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($) affiliate insurer	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Related party transactions
Management fee rate as a percent of direct and affiliated assumed written premiums of the Exchange			25.00%
Minimum number of affiliates to be classified as an insurance holding company system | affiliate			2
Minimum number of insurer affiliates to be classified as an insurance holding company system | insurer			1
Total operating revenue			$ 2,840,124	$ 2,633,977	$ 2,536,489
Service agreement revenue
Related party transactions
Total operating revenue			$ 25,687	$ 24,042	$ 25,797
Erie Insurance Exchange (EIE)
Related party transactions
Management fee rate as a percent of direct and affiliated assumed written premiums of the Exchange			25.00%	25.00%	25.00%
Payment to acquire real estate				$ 97,500
Lease expense on office space leased from Exchange				6,100	$ 6,100
Operating expenses on shared facilities		$ 800	$ 19,500	15,700	15,700
Reimbursements from the Exchange for shared facilities		100	4,100	$ 4,800	$ 4,600
Erie Insurance Exchange (EIE) | Subsequent Event
Related party transactions
Management fee rate as a percent of direct and affiliated assumed written premiums of the Exchange	25.00%
Erie Insurance Exchange (EIE) | Service agreement revenue
Related party transactions
Total operating revenue		$ 200	$ 2,200