Organization (Details)	6 Months Ended
Jun. 30, 2025 Segment
Organization [Abstract]
Number of operating segments (in Segment)	3
Donegal Mutual Insurance Company [Member]
Organization [Abstract]
Voting power percentage of outstanding common stock	70.00%
Premiums and losses related to certain products	100.00%
Atlantic States [Member]
Organization [Abstract]
Percentage of share in results of pooled business subsidiary	80.00%
Class A Common Stock [Member] \| Donegal Mutual Insurance Company [Member]
Organization [Abstract]
Stock ownership percentage held by major shareholder	44.00%
Class B Common Stock [Member] \| Donegal Mutual Insurance Company [Member]
Organization [Abstract]
Stock ownership percentage held by major shareholder	84.00%

The percentage of share in results of pooled business subsidiary.

No definition available.

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- Definition

The percentage of voting power owned by major shareholder.

+ References

No definition available.

+ Details

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- Definition

The percentage of stock ownership held by major shareholder.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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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/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 49
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-49

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-18

+ Details

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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
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column F))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477965/944-235-S99-2

+ Details

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- Details

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- Details

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- Details

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- Details

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