Organization (Details)	3 Months Ended
Mar. 31, 2023 Segment
Organization [Abstract]
Number of operating segments	3
Atlantic States [Member]
Organization [Abstract]
Percentage of share in results of pooled business subsidiary	80.00%
Donegal Mutual Insurance Company [Member]
Organization [Abstract]
Voting power percentage of outstanding common stock	71.00%
Premiums and losses related to certain products	100.00%
Donegal Mutual Insurance Company [Member] \| Class A Common Stock [Member]
Organization [Abstract]
Stock ownership percentage held by major shareholder	43.00%
Donegal Mutual Insurance Company [Member] \| Class B Common Stock [Member]
Organization [Abstract]
Stock ownership percentage held by major shareholder	84.00%

No definition available.

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- Definition

The percentage of share in results of pooled business subsidiary.

+ References

No definition available.

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- Definition

The percentage of voting power owned by major shareholder.

+ References

No definition available.

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The percentage of stock ownership held by major shareholder.

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No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599

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- Definition

Percentage of assumed premium earned to premium earned after effects of reinsurance, as disclosed in supplementary reinsurance information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column F))
-URI https://asc.fasb.org/extlink&oid=120401096&loc=d3e574992-122915

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