Note 2 - Investment Securities (Tables)

12 Months Ended

Dec. 31, 2012

Unrealized Gain (Loss) on Investments [Table Text Block]

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Fair Value
December 31, 2012:
Securities held to maturity:
Municipal securities	$	71,429,385	$	997,969	$	(71,648	)	$	72,355,706
Other securities		650,000		-		-			650,000
	$	72,079,385	$	997,969	$	(71,648	)	$	73,005,706
Securities available for sale:
U.S. govt. sponsored agency securities	$	336,570,995	$	2,198,655	$	(160,279	)	$	338,609,371
Residential mortgage-backed and related securities		160,035,196		3,736,821		(170,914	)		163,601,103
Municipal securities		24,508,015		1,696,555		(18,834	)		26,185,736
Trust preferred securities		86,200		53,200		-			139,400
Other securities		1,347,113		300,732		(23,469	)		1,624,376
	$	522,547,519	$	7,985,963	$	(373,496	)	$	530,159,986
December 31, 2011:
Securities held to maturity:
Other securities	$	200,000	$	-	$	-		$	200,000
Securities available for sale:
U.S. govt. sponsored agency securities	$	426,581,913	$	2,428,994	$	(55,687	)	$	428,955,220
Residential mortgage-backed and related securities		105,373,614		3,488,350		(8,215	)		108,853,749
Municipal securities		23,937,118		1,752,246		-			25,689,364
Trust preferred securities		86,200		-		(5,400	)		80,800
Other securities		1,354,940		140,022		(44,804	)		1,450,158
	$	557,333,785	$	7,809,612	$	(114,106	)	$	565,029,291

Schedule of Unrealized Loss on Investments [Table Text Block]

	Less than 12 Months					12 Months or More					Total
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
December 31, 2012:
Securities held to maturity:
Municipal securities	$	4,282,352	$	(71,648	)	$	-	$	-		$	4,282,352	$	(71,648	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	55,621,718	$	(160,279	)	$	-	$	-		$	55,621,718	$	(160,279	)
Residential mortgage-backed and related securities		29,324,928		(170,914	)		-		-			29,324,928		(170,914	)
Municipal securities		1,039,625		(18,834	)		-		-			1,039,625		(18,834	)
Other securities		-		-			217,500		(23,469	)		217,500		(23,469	)
	$	85,986,271	$	(350,027	)	$	217,500	$	(23,469	)	$	86,203,771	$	(373,496	)
December 31, 2011:
Securities available for sale:
U.S. govt. sponsored agency securities	$	59,979,620	$	(55,687	)	$	-	$	-		$	59,979,620	$	(55,687	)
Residential mortgage-backed and related securities		4,906,398		(8,215	)		-		-			4,906,398		(8,215	)
Trust preferred securities		-		-			80,800		(5,400	)		80,800		(5,400	)
Other securities		251,957		(44,332	)		2,778		(472	)		254,735		(44,804	)
	$	65,137,975	$	(108,234	)	$	83,578	$	(5,872	)	$	65,221,553	$	(114,106	)

Realized Gain (Loss) on Investments [Table Text Block]

	2012		2011		2010
Proceeds from sales of securities	$	19,215,075	$	54,326,191	$	-
Gross gains from sales of securities		104,600		1,472,528		-

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Securities held to maturity:
Due in one year or less	$	853,965	$	858,014
Due after one year through five years		9,801,254		9,813,395
Due after five years		61,424,166		62,334,297
	$	72,079,385	$	73,005,706
Securities available for sale:
Due in one year or less	$	995,005	$	995,917
Due after one year through five years		33,202,789		33,663,178
Due after five years		326,967,416		330,275,412
	$	361,165,210	$	364,934,507
Residential mortgage-backed and related securities		160,035,196		163,601,103
Other securities		1,347,113		1,624,376
	$	522,547,519	$	530,159,986

	Amortized Cost		Fair Value
Municipal securities, held to maturity	$	46,672,253	$	47,157,578
U.S. govt. sponsored agency securities		304,670,224		306,253,738
Municipal securities, available for sale		13,498,939		14,381,300
	$	318,169,163	$	320,635,038