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Number of states in which marketing of the products has been started.

No definition available.

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- References

No definition available.

Name:	dgica_OrganizationAndBusinessAbstract
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The percentage of share in results of pooled business subsidiary.

No definition available.

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The percentage of voting power owned by major shareholder.

No definition available.

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The percentage of stock ownership held by major shareholder.

No definition available.

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- References

No definition available.

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- References

No definition available.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=SL79508275-113901

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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.

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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Data Type:	xbrli:integerItemType
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Percentage of assumed premium earned to premium earned after effects of reinsurance, as disclosed in supplementary reinsurance information.

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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Data Type:	dtr-types:percentItemType
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Name:	dei_LegalEntityAxis=dgica_AtlanticStatesMember
Namespace Prefix:
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Name:	srt_ConsolidatedEntitiesAxis=dgica_DonegalMutualInsuranceCompanyMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix:
Data Type:	na
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