Note 3 - Investment Securities (Details) - Gross Unrealized Losses and Fair value of Securities in a Continuous Unrealized Loss Position (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Securities held to maturity:
Held to Maturity Securities less than 12 months fair value	$ 93,281,343
Held to Maturity Securities less than 12 months gross unrealized losses	(6,525,639)
Held to Maturity Securities fair value	93,281,343
Held to Maturity Securities gross unrealized losses	(6,525,639)
Securities available for sale:
Available for Sale Securities less than 12 months fair value	474,158,854	85,986,271
Available for Sale Securities less than 12 months gross unrealized losses	(19,023,591)	(350,027)
Available for Sale Securities 12 months or more fair value	1,279,117	217,500
Available for Sale Securities 12 months or more gross unrealized losses	(15,478)	(23,469)
Available for Sale Securities fair value	475,437,971	86,203,771
Available for Sale Securities gross unrealized losses	(19,039,069)	(373,496)
US States and Political Subdivisions Debt Securities [Member]
Securities held to maturity:
Held to Maturity Securities less than 12 months fair value	92,786,083	4,282,352
Held to Maturity Securities less than 12 months gross unrealized losses	(6,520,899)	(71,648)
Held to Maturity Securities 12 months or more fair value	0	0
Held to Maturity Securities 12 months or more gross unrealized losses	0	0
Held to Maturity Securities fair value	92,786,083	4,282,352
Held to Maturity Securities gross unrealized losses	(6,520,899)	(71,648)
Securities available for sale:
Available for Sale Securities less than 12 months fair value	16,263,130	1,039,625
Available for Sale Securities less than 12 months gross unrealized losses	(761,791)	(18,834)
Available for Sale Securities 12 months or more fair value	0	0
Available for Sale Securities 12 months or more gross unrealized losses	0	0
Available for Sale Securities fair value	16,263,130	1,039,625
Available for Sale Securities gross unrealized losses	(761,791)	(18,834)
Equity Securities, Other [Member]
Securities held to maturity:
Held to Maturity Securities less than 12 months fair value	495,260
Held to Maturity Securities less than 12 months gross unrealized losses	(4,740)
Held to Maturity Securities fair value	495,260
Held to Maturity Securities gross unrealized losses	(4,740)
Securities available for sale:
Available for Sale Securities less than 12 months fair value		0
Available for Sale Securities less than 12 months gross unrealized losses		0
Available for Sale Securities 12 months or more fair value		217,500
Available for Sale Securities 12 months or more gross unrealized losses		(23,469)
Available for Sale Securities fair value		217,500
Available for Sale Securities gross unrealized losses		(23,469)
US Government Agencies Debt Securities [Member]
Securities available for sale:
Available for Sale Securities less than 12 months fair value	351,006,164	55,621,718
Available for Sale Securities less than 12 months gross unrealized losses	(15,744,151)	(160,279)
Available for Sale Securities 12 months or more fair value	0	0
Available for Sale Securities 12 months or more gross unrealized losses	0	0
Available for Sale Securities fair value	351,006,164	55,621,718
Available for Sale Securities gross unrealized losses	(15,744,151)	(160,279)
Residential Mortgage Backed Securities [Member]
Securities available for sale:
Available for Sale Securities less than 12 months fair value	106,889,560	29,324,928
Available for Sale Securities less than 12 months gross unrealized losses	(2,517,649)	(170,914)
Available for Sale Securities 12 months or more fair value	1,279,117	0
Available for Sale Securities 12 months or more gross unrealized losses	(15,478)	0
Available for Sale Securities fair value	108,168,677	29,324,928
Available for Sale Securities gross unrealized losses	$ (2,533,127)	$ (170,914)