Consolidated Statements Of Stockholders' Equity (USD $)	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Total
Balance at Dec. 31, 2009	$ 1	$ 92,528,818	$ 4,730,258	$ 97,259,077
Balance, shares at Dec. 31, 2009	2,285,289
Net income		6,372,626		6,372,626
Dividends ($.28 per share)		(639,734)		(639,734)
Shares of common stock repurchased and retired		(378,770)		(378,770)
Shares of common stock repurchased and retired, shares	(12,138)
Stock options exercised		140,500		140,500
Stock options exercised, shares	9,445
Share-based compensation expense		216,669		216,669
Amortization related to postretirement health benefits			15,160	15,160
Accumulated postretirement benefit obligation adjustment			107,913	107,913
Net unrealized gain on investments			835,374	835,374
Balance at Dec. 31, 2010	1	98,240,109	5,688,705	103,928,815
Balance, shares at Dec. 31, 2010	2,282,596
Net income		6,933,936		6,933,936
Dividends ($.28 per share)		(599,241)		(599,241)
Shares of common stock repurchased and retired		(5,940,463)		(5,940,463)
Shares of common stock repurchased and retired, shares	(182,615)
Stock options exercised		155,163		155,163
Stock options exercised, shares	7,700
Share-based compensation expense		213,514		213,514
Amortization related to postretirement health benefits			8,394	8,394
Accumulated postretirement benefit obligation adjustment			(75,959)	(75,959)
Net unrealized gain on investments			1,888,025	1,888,025
Balance at Dec. 31, 2011	$ 1	$ 99,003,018	$ 7,509,165	$ 106,512,184
Balance, shares at Dec. 31, 2011	2,107,681