Note 2 - Investment Securities (Details) - Amortized Cost and Fair Value of Investment Securities (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Securities held to maturity:
Securities held to maturity, amortized cost	$ 161,629,152	$ 145,451,895
Securities held to maturity, gross unrealized gains	756,828	299,789
Securities held to maturity, gross unrealized losses	(4,768,120)	(7,111,579)
Securities held to maturity, fair value	157,617,860	138,640,105
Securities available for sale:
Available for Sale Securities, amortized cost	559,120,092	573,870,562
Available for Sale Securities, gross unrealized gains	2,971,800	2,643,218
Available for Sale Securities, gross unrealized losses	(16,614,355)	(24,755,322)
Available for Sale Securities, fair value	545,477,537	551,758,458
US States and Political Subdivisions Debt Securities [Member]
Securities held to maturity:
Securities held to maturity, amortized cost	160,579,152	144,401,895
Securities held to maturity, gross unrealized gains	756,828	299,789
Securities held to maturity, gross unrealized losses	(4,768,120)	(7,111,579)
Securities held to maturity, fair value	156,567,860	137,590,105
Securities available for sale:
Available for Sale Securities, amortized cost	34,495,776	35,813,866
Available for Sale Securities, gross unrealized gains	997,316	923,315
Available for Sale Securities, gross unrealized losses	(417,026)	(778,324)
Available for Sale Securities, fair value	35,076,066	35,958,857
Other Securities [Member]
Securities held to maturity:
Securities held to maturity, amortized cost	1,050,000	1,050,000
Securities held to maturity, gross unrealized gains	0	0
Securities held to maturity, gross unrealized losses	0	0
Securities held to maturity, fair value	1,050,000	1,050,000
Securities available for sale:
Available for Sale Securities, amortized cost	1,378,550	1,372,365
Available for Sale Securities, gross unrealized gains	565,961	524,798
Available for Sale Securities, gross unrealized losses	0	0
Available for Sale Securities, fair value	1,944,511	1,897,163
US Government Agencies Debt Securities [Member]
Securities available for sale:
Available for Sale Securities, amortized cost	363,901,863	376,574,132
Available for Sale Securities, gross unrealized gains	31,503	41,696
Available for Sale Securities, gross unrealized losses	(13,595,807)	(20,142,841)
Available for Sale Securities, fair value	350,337,559	356,472,987
Residential Mortgage Backed Securities [Member]
Securities available for sale:
Available for Sale Securities, amortized cost	159,343,903	160,110,199
Available for Sale Securities, gross unrealized gains	1,377,020	1,153,409
Available for Sale Securities, gross unrealized losses	(2,601,522)	(3,834,157)
Available for Sale Securities, fair value	$ 158,119,401	$ 157,429,451