Segment Information - Summary of Financial Data by Segment (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Premiums earned
Net premiums earned	$ 136,589,156	$ 126,963,328	$ 270,137,417	$ 251,665,369
GAAP premiums earned	136,589,000	126,963,000	270,137,000	251,665,000
Net investment income	4,614,484	4,670,558	9,230,260	9,486,001
Realized investment gains	2,034,172	1,253,982	1,945,640	2,594,546
Equity in earnings of DFSC	348,625	675,568	757,867	1,764,474
Other	1,896,000	1,944,000	3,750,000	3,870,000
Total revenues	145,481,928	135,507,635	285,821,015	269,380,227
Underwriting loss:
SAP underwriting income (loss)	(8,952,000)	(6,527,000)	(18,134,000)	(7,894,000)
GAAP adjustments	3,475,000	2,591,000	6,400,000	4,340,000
GAAP underwriting loss	(5,477,000)	(3,936,000)	(11,734,000)	(3,554,000)
Net investment income	4,614,000	4,671,000	9,230,000	9,486,000
Realized investment gains	2,034,172	1,253,982	1,945,640	2,594,546
Equity in earnings of DFSC	348,625	675,568	757,867	1,764,474
Other	800,000	197,000	1,327,000	654,000
Income before income tax expense	2,319,912	2,862,158	1,526,696	10,945,447
Commercial lines [Member]
Premiums earned
Net premiums earned	56,696,000	49,612,000	111,042,000	97,243,000
Underwriting loss:
GAAP underwriting loss	(5,827,000)	(3,079,000)	(11,175,000)	(4,670,000)
Personal lines [Member]
Premiums earned
Net premiums earned	79,893,000	77,351,000	159,095,000	154,422,000
Underwriting loss:
GAAP underwriting loss	$ (3,125,000)	$ (3,448,000)	$ (6,959,000)	$ (3,224,000)