Fair Value Measurements (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	$ 703,267,079	$ 654,035,716
Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	703,267,079	654,035,716
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	5,365,721	6,178,136
Significant Other Observable Inputs (Level 2) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	697,901,358	647,857,580
Significant Unobservable Inputs (Level 3) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure
U.S. Treasury securities and obligations of U.S. government corporations and agencies [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	71,311,103	60,977,557
U.S. Treasury securities and obligations of U.S. government corporations and agencies [Member] | Significant Other Observable Inputs (Level 2) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	71,311,103	60,977,557
U.S. Treasury securities and obligations of U.S. government corporations and agencies [Member] | Significant Unobservable Inputs (Level 3) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure
Obligations of states and political subdivisions [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	416,986,963	398,876,582
Obligations of states and political subdivisions [Member] | Significant Other Observable Inputs (Level 2) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	416,986,963	398,876,582
Obligations of states and political subdivisions [Member] | Significant Unobservable Inputs (Level 3) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure
Corporate securities [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	77,355,777	64,113,649
Corporate securities [Member] | Significant Other Observable Inputs (Level 2) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	77,355,777	64,113,649
Corporate securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure
Residential mortgage-backed securities [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	128,855,978	122,630,390
Residential mortgage-backed securities [Member] | Significant Other Observable Inputs (Level 2) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	128,855,978	122,630,390
Residential mortgage-backed securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure
Equity securities [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	8,757,258	7,437,538
Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	5,365,721	6,178,136
Equity securities [Member] | Significant Other Observable Inputs (Level 2) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure	3,391,537	1,259,402
Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | Assets and liabilities on recurring basis [Member]
Fair value measurements for investments in available-for-sale fixed maturity and equity securities
Available-for-sale Securities, Fair Value Disclosure