Consolidated Statements of Income - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
Net premiums earned	$ 177,283,816	$ 166,809,851	$ 521,454,835	$ 487,227,767
Investment income, net of investment expenses	5,979,834	5,581,238	17,385,103	16,471,630
Net realized investment gains	561,429	1,018,415	4,207,710	2,204,533
Lease income	113,409	163,779	383,183	514,768
Installment payment fees	1,373,892	1,380,024	3,813,663	4,109,550
Equity in earnings of Donegal Financial Services Corporation	403,647	357,956	1,023,212	698,658
Total revenues	185,716,027	175,311,263	548,267,706	511,226,906
Expenses:
Net losses and loss expenses	114,386,379	111,174,963	356,825,751	309,946,943
Amortization of deferred policy acquisition costs	29,008,000	27,524,000	85,391,000	80,034,000
Other underwriting expenses	31,790,251	28,340,135	88,538,755	81,557,159
Policyholder dividends	1,376,115	1,143,026	3,422,672	2,729,595
Interest	466,262	473,917	1,212,895	1,286,279
Other expenses	176,970	226,183	1,036,223	1,179,660
Total expenses	177,203,977	168,882,224	536,427,296	476,733,636
Income before income tax expense	8,512,050	6,429,039	11,840,410	34,493,270
Income tax expense	1,403,476	1,615,635	1,945,666	9,246,299
Net income	$ 7,108,574	$ 4,813,404	$ 9,894,744	$ 25,246,971
Class A Common Stock [Member]
Earnings per common share:
Common stock-basic	$ 0.27	$ 0.19	$ 0.37	$ 0.98
Common stock-diluted	0.26	0.18	0.36	0.95
Class B Common Stock [Member]
Earnings per common share:
Common stock-basic	0.24	0.16	0.33	0.88
Common stock-diluted	0.24	0.16	0.33	0.88
Common stock-basic and diluted	$ 0.24	$ 0.16	$ 0.33	$ 0.88