Postretirement Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Cost of pension plans:
Service cost for benefits earned	$ 7,191	$ 12,561	$ 14,382	$ 25,121
Interest cost on benefit obligation	12,548	9,941	25,096	19,882
Expected return on plan assets	(17,217)	(13,639)	(34,435)	(27,278)
Prior service cost amortization	361	360	723	721
Net actuarial (gain) loss amortization	(3,832)	1,830	(7,665)	3,660
Pension plan (income) cost	$ (949)	$ 11,053	$ (1,899)	$ 22,106
Defined benefit plan, net periodic benefit cost (credit) excluding service cost, statement of income or comprehensive income			Other income
Employee pension plan | Funded Plan | Qualified Plan
Postretirement Benefits
Funding target (as a percentage of the funding target liability)	100.00%		100.00%
Expected future employer contributions	$ 95,000		$ 95,000
Erie Insurance Exchange | Employee pension plan | Funded Plan | Qualified Plan
Postretirement Benefits
Postretirement annual benefit income and expense reimbursed to and from, respectively, the Exchange and its subsidiaries (as a percent)			60.00%
Erie Insurance Exchange | Supplemental employee retirement plan (SERP) | Unfunded Plan | Nonqualified Plan
Postretirement Benefits
Postretirement annual benefit income and expense reimbursed to and from, respectively, the Exchange and its subsidiaries (as a percent)			36.00%