Consolidated Statements of Changes in Stockholders' Equity (unaudited) (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at beginning of period at Dec. 31, 2009	$ 81,608,453	$ 24,582,675	$ 15,768,840	$ 42,518,889	$ (1,261,951)
Balance (in shares) at Dec. 31, 2009		4,916,535
Comprehensive income:
Net income	1,096,979	0	0	1,096,979	0
Unrealized holding gains arising during the period	1,101,602	0	0	0	1,101,602
Total comprehensive income	2,198,581	0	0	1,096,979	1,101,602
Exercise of stock options (in shares)		23,874
Exercise of stock options	245,884	119,370	126,514	0	0
Tax benefit from disqualification of stock options	16,324	0	16,324	0	0
Repurchase and retirement of common stock (in shares)		(3,420)
Repurchase and retirement of common stock	(41,074)	(17,100)	0	(23,974)	0
Stock compensation expense	85,398	0	85,398	0	0
Cash dividends	(985,124)	0	0	(985,124)	0
Balance at end of period at Sep. 30, 2010	83,128,442	24,684,945	15,997,076	42,606,770	(160,349)
Balance (in shares) at Sep. 30, 2010		4,936,989
Balance at beginning of period at Dec. 31, 2010	80,951,649	24,684,945	16,026,062	42,809,769	(2,569,127)
Balance (in shares) at Dec. 31, 2010	4,936,989	4,936,989
Comprehensive income:
Net income	2,423,233	0	0	2,423,233	0
Unrealized holding gains arising during the period	2,343,432	0	0	0	2,343,432
Total comprehensive income	4,766,665	0	0	2,423,233	2,343,432
Exercise of stock options (in shares)		22,020
Exercise of stock options	284,205	110,100	174,105	0	0
Stock compensation expense	82,466	0	82,466	0	0
Cash dividends	(742,563)	0	0	(742,563)	0
Balance at end of period at Sep. 30, 2011	$ 85,342,422	$ 24,795,045	$ 16,282,633	$ 44,490,439	$ (225,695)
Balance (in shares) at Sep. 30, 2011	4,959,009	4,959,009