Contingent consideration from sale of business.

No definition available.

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- Definition

Percentage of share in results of pooled business owned by third party.

+ References

No definition available.

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- Definition

Percentage of share in results of pooled business subsidiary.

+ References

No definition available.

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- Definition

Percentage of voting power owned by major shareholder.

+ References

No definition available.

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- Definition

Shares received as consideration.

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No definition available.

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- Definition

Stock ownership percentage held by major shareholder.

+ References

No definition available.

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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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- Definition

Carrying amount as of the balance sheet date of dividends declared but not received.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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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.

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- Definition

The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

+ References

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.

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No definition available.

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Date the operations of the entity commenced, in CCYY-MM-DD format.

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No definition available.

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- Definition

Dividends received on equity and other investments during the current period.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Organization - Additional Information (Detail) $ in Millions	3 Months Ended	80 Months Ended
	Mar. 31, 2020 USD ($) Segment	Mar. 31, 2020 shares	Mar. 08, 2019 USD ($)	Jul. 18, 2013 shares
Business Acquisition [Line Items]
Operations commenced date	Aug. 26, 1986
Number of operating segments \| Segment	3
Voting power percentage of outstanding common stock	71.00%
Atlantic States [Member]
Business Acquisition [Line Items]
Percentage of share in results of pooled business subsidiary	80.00%
Donegal Mutual [Member]
Business Acquisition [Line Items]
Percentage of share in results of pooled business owned by third party	20.00%
DFSC and North West [Member]
Business Acquisition [Line Items]
Consideration from sale of business	$ 20.5
Consideration from sale of business fair value at closing date	20.9
DFSC and North West [Member] \| Donegal Mutual Insurance Company [Member]
Business Acquisition [Line Items]
Consideration from sale of business	85.8
Proceeds from dividend	$ 29.2
Donegal Financial Services Corporation [Member]
Business Acquisition [Line Items]
Outstanding stock ownership percentage	48.20%	48.20%
Gain (Loss) on Sale of Equity Investments	$ 12.7
Donegal Financial Services Corporation [Member] \| DFSC and North West [Member]
Business Acquisition [Line Items]
Dividend payment to be received			$ 14.1
Class A Common Stock [Member]
Business Acquisition [Line Items]
Stock ownership percentage held by major shareholder	42.00%
Class A Common Stock [Member] \| Stock Repurchase Program Two [Member]
Business Acquisition [Line Items]
Authority to purchase shares \| shares				500,000
Common stock shares purchased \| shares		57,658
Class B Common Stock [Member]
Business Acquisition [Line Items]
Stock ownership percentage held by major shareholder	84.00%