Aggregate fair value of bond held.

No definition available.

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- Definition

Amortized cost of bond held.

+ References

No definition available.

+ Details

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- Definition

Number of securities classified as available for sale in unrealized loss position.

+ References

No definition available.

+ Details

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- Definition

Percentage of different kind of bond included in investment in special revenue bonds.

+ References

No definition available.

+ Details

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- Definition

Reclassification Adjustment Out Of Accumulated Other Comprehensive Income Amortization Of Unrecognized Loss

+ References

No definition available.

+ Details

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- Definition

Threshold limit for investment held.

+ References

No definition available.

+ Details

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- Definition

Time period for which individual security should be in unrealized position of twenty percentage or more to assume it as other than temporary decline.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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- Definition

This item represents the percentage of nonperforming assets that the underlying assets in the security represent and which were considered as one of the potential factors in reaching a conclusion that the held-to-maturity investments are other than temporarily impaired and only the amount of impairment related to credit loss was recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8A
-Subparagraph a.3.
-URI http://asc.fasb.org/extlink&oid=73527792&loc=SL6284381-111563

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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

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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.

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- Details

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Investments - Additional Information (Detail)		3 Months Ended		12 Months Ended
Investments - Additional Information (Detail)	Nov. 30, 2013 USD ($)	Mar. 31, 2017 USD ($) Securities	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Schedule of Investments [Line Items]
Net unrealized losses arising prior to reclassification date and classified in accumulated other comprehensive loss	$ 15,100,000
Amortization of unrealized losses recorded in accumulated other comprehensive income		$ 296,659	$ 368,497
Depreciation of original cost value		20.00%
Time period for which individual security should be in unrealized position of twenty percentage or more to assume it as other than temporary decline		More than six months
Donegal Financial Services Corporation [Member]
Schedule of Investments [Line Items]
Percentage of ownership interest		48.20%
Equity Securities [Member]
Schedule of Investments [Line Items]
Number of fixed maturity securities classified as available for sale \| Securities		9
Obligations of States and Political Subdivisions [Member]
Schedule of Investments [Line Items]
Aggregate fair value of bond held		$ 216,600,000		$ 220,100,000
Amortized cost of bond held		207,400,000		211,000,000
Special Revenue Bonds [Member]
Schedule of Investments [Line Items]
Aggregate fair value of bond held		95,800,000		96,800,000
Amortized cost of bond held		$ 90,600,000		$ 91,700,000
Education Bonds [Member]
Schedule of Investments [Line Items]
Percentage of investments in special revenue bonds		58.00%		62.00%
Water and Sewer Utility Bonds [Member]
Schedule of Investments [Line Items]
Percentage of investments in special revenue bonds		23.00%		23.00%
Fixed Maturities [Member]
Schedule of Investments [Line Items]
Number of fixed maturity securities classified as available for sale \| Securities		242
Accumulated Net Unrealized Investment Losses [Member]
Schedule of Investments [Line Items]
Net unrealized losses reclassified in accumulated other comprehensive(loss) income		$ 10,700,000	$ 11,000,000
Minimum [Member]
Schedule of Investments [Line Items]
Percentage of which the company held security of any issuer		10.00%		10.00%