CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Investments:
Securities available-for-sale, amortized cost	$ 920,194,233	$ 920,843,939
Equity securities available-for-sale, cost	114,539,282	111,851,963
Deferred policy acquisition costs from affiliates	34,239,791	34,425,593
Affiliated other assets	6,679,412	5,760,369
LIABILITIES
Affiliated losses and settlement expenses	579,163,850	577,476,988
Unearned premiums from affiliates	199,219,701	196,215,465
Affiliated other liabilities	$ 13,498,920	$ 22,794,304
STOCKHOLDERS' EQUITY
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares issued (in shares)	12,992,835	12,909,457
Common stock, shares outstanding (in shares)	12,992,835	12,909,457