Note 2 - Investment Securities (Details) - Amortized Cost and Fair Value of Securities by Contractual Maturity (USD $)	Jun. 30, 2014	Dec. 31, 2013
Securities held to maturity:
Due in one year or less	$ 2,927,386
Due in one year or less	2,929,942
Due after one year through five years	10,861,031
Due after one year through five years	10,874,917
Due after five years	152,998,955
Due after five years	151,865,468
	166,787,372
	165,670,327	138,640,105
Securities available for sale:
Due in one year or less	4,485,092
Due in one year or less	4,498,204
Due after one year through five years	48,898,104
Due after one year through five years	48,717,600
Due after five years	313,572,065
Due after five years	306,262,123
	366,955,261
	359,477,927
Amortized Cost	521,322,159
Fair Value	515,335,097
Residential Mortgage Backed Securities [Member]
Securities available for sale:
Amortized Cost	152,965,071
Fair Value	153,895,214
Other Securities [Member]
Securities held to maturity:
	1,050,000	1,050,000
Securities available for sale:
Amortized Cost	1,401,827
Fair Value	1,961,956
US States and Political Subdivisions Debt Securities [Member]
Securities held to maturity:
	164,620,327	137,590,105
US States and Political Subdivisions Debt Securities [Member] | Callable Securities [Member]
Securities available for sale:
Amortized Cost	20,829,274
Fair Value	21,268,094
Securities held to maturity:
Municipal securities	102,919,232
Municipal securities	102,260,651
US Government-sponsored Enterprises Debt Securities [Member] | Callable Securities [Member]
Securities available for sale:
Amortized Cost	271,663,942
Fair Value	264,421,214
Callable Securities [Member]
Securities available for sale:
Amortized Cost	292,493,216
Fair Value	$ 285,689,308