Consolidated Statements Of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 2,440,465	$ 1,449,101	$ 5,054,477	$ 4,004,076
Other comprehensive income, before tax:
Amortization related to prior year service cost	(415)	5,097	9,779	15,291
Amortization of unrecognized (loss) gain	(1,525)	645	(239)	1,929
Unrealized (losses) gains on investments arising during the period	(1,217,304)	2,786,823	543,683	2,898,570
Reclassification adjustment for sale of securities included in net income	49,979	(1,477)	(179,309)	(437,301)
Reclassification adjustment for write down of securities included in net income	150,108	46,341	258,481	131,235
Other comprehensive (loss) income, before tax	(1,019,157)	2,837,429	632,395	2,609,724
Income tax (benefit) expense related to postretirement health benefits	(661)	1,956	3,244	5,855
Income tax (benefit) expense related to unrealized (losses) gains on investments arising during the year	(427,839)	956,357	170,908	1,002,295
Income tax expense (benefit) related to reclassification adjustment for sale of securities included in net income	17,377	(340)	(61,842)	(152,395)
Income tax expense related to reclassification adjustment for write down of securities included in net income	51,612	15,752	89,888	46,315
Net income tax (benefit) expense on other comprehensive income	(359,511)	973,725	202,198	902,070
Other comprehensive (loss) income	(659,646)	1,863,704	430,197	1,707,654
Comprehensive income	$ 1,780,819	$ 3,312,805	$ 5,484,674	$ 5,711,730