CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) (USD $)	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balances at Dec. 31, 2011	$ 53,101	$ 45,582,861	$ 100,628,900	$ (18,894,044)	$ (1,441,378)	$ 125,929,440
Net income	0	0	6,058,573	0	0	6,058,573
Other comprehensive income	0	0	0	0	585,352	585,352
Restricted stock awards	0	44,743	0	0	0	44,743
Restricted stock units for directors' deferred compensation plan	0	42,982	0	0	0	42,982
Cash dividends declared	0	0	(2,286,005)	0	0	(2,286,005)
Distribution of shares of treasury stock for directors' compensation	0	(28,121)	0	261,069	0	232,948
Distribution of shares of treasury stock for employee compensation	0	(8,052)	0	88,052	0	80,000
Distribution of shares of treasury stock for deferred directors' compensation	0	(81,747)	0	82,588	0	841
Distribution of shares of treasury stock granted for employee restricted stock awards	0	(27,514)	0	27,514	0	0
Purchase of shares of treasury stock	0	0	0	(480,073)	0	(480,073)
Balances at Jun. 30, 2012	53,101	45,525,152	104,401,468	(18,914,894)	(856,026)	130,208,801
Balances at Dec. 31, 2012	53,101	45,357,073	107,078,182	(18,566,490)	(2,806,929)	131,114,937
Net income	0	0	5,066,375	0	0	5,066,375
Other comprehensive income	0	0	0	0	(1,568,118)	(1,568,118)
Restricted stock awards	0	85,494	0	0	0	85,494
Restricted stock units for directors' deferred compensation plan	0	50,925	0	0	0	50,925
Cash dividends declared	0	0	(2,389,105)	0	0	(2,389,105)
Distribution of shares of treasury stock for directors' compensation	0	13,896	0	203,050	0	216,946
Distribution of shares of treasury stock for employee compensation	0	7,278	0	104,876	0	112,154
Distribution of shares of treasury stock for deferred directors' compensation	0	(74,623)	0	85,577	0	10,954
Purchase of shares of treasury stock	0	0	0	(92,630)	0	(92,630)
Sale of treasury stock	0	10,518	0	60,362	0	70,880
Balances at Jun. 30, 2013	$ 53,101	$ 45,450,561	$ 109,755,452	$ (18,205,255)	$ (4,375,047)	$ 132,678,812