Represents the percentage at which 401(k) matching contributions are reimbursed to the attorney-in-fact.

No definition available.

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- Definition

The number of employer shares or related party shares included in the defined contribution plan assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	erie_
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Balance Type:	na
Period Type:	instant

- Definition

[Line Items] for Schedule of Defined Contribution Plans Disclosures [Table]

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Postretirement Benefits - Employee Savings Plan (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Employee savings plan
Employer matching contribution paid to the plan	$ 18.4	$ 16.7	$ 16.1
Class A common stock held by plan participants (in shares)	0.1	0.1
Erie Insurance Exchange (EIE)
Employee savings plan
Matching contributions reimbursed to Indemnity from the Exchange and its subsidiaries (as a percent)	59.00%
100% employer matching contribution
Employee savings plan
Percentage of employer matching contribution of employee contributions	100.00%
100% employer matching contribution \| Maximum
Employee savings plan
Percentage of eligible employee compensation, matched by employer	3.00%
50% employer matching contribution
Employee savings plan
Percentage of employer matching contribution of employee contributions	50.00%
50% employer matching contribution \| Maximum
Employee savings plan
Percentage of eligible employee compensation, matched by employer	5.00%
50% employer matching contribution \| Minimum
Employee savings plan
Percentage of eligible employee compensation, matched by employer	3.00%