Note 2 - Investment Securities (Tables)

3 Months Ended

Mar. 31, 2013

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

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Fair Value
March 31, 2013:
Securities held to maturity:
Municipal securities	$	86,356,209	$	746,173	$	(407,348	)	$	86,695,034
Other securities		650,000		-		-			650,000
	$	87,006,209	$	746,173	$	(407,348	)	$	87,345,034
Securities available for sale:
U.S. govt. sponsored agency securities	$	402,488,606	$	1,769,562	$	(418,236	)	$	403,839,932
Residential mortgage-backed and related securities		171,863,065		3,381,118		(441,951	)		174,802,232
Municipal securities		23,485,794		1,543,985		(38,738	)		24,991,041
Trust preferred securities		86,200		99,120		-			185,320
Other securities		1,365,794		366,719		(5,664	)		1,726,849
	$	599,289,459	$	7,160,504	$	(904,589	)	$	605,545,374
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

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
March 31, 2013:
Securities held to maturity:
Municipal securities	$	25,634,890	$	(407,348	)	$	-	$	-		$	25,634,890	$	(407,348	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	129,197,592	$	(418,236	)	$	-	$	-		$	129,197,592	$	(418,236	)
Residential mortgage-backed and related securities		46,924,954		(441,951	)		-		-			46,924,954		(441,951	)
Municipal securities		2,223,597		(38,738	)		-		-			2,223,597		(38,738	)
Other securities		-		-			235,625		(5,664	)		235,625		(5,664	)
	$	178,346,143	$	(898,925	)	$	235,625	$	(5,664	)	$	178,581,768	$	(904,589	)
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	)

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Securities held to maturity:
Due in one year or less	$	1,465,502	$	1,465,266
Due after one year through five years		13,406,654		13,426,853
Due after one year through five years		72,134,053		72,452,915
	$	87,006,209	$	87,345,034
Securities available for sale:
Due in one year or less	$	695,000	$	700,650
Due after one year through five years		29,282,063		29,712,248
Due after five years		396,083,537		398,603,395
	$	426,060,600	$	429,016,293
Residential mortgage-backed and related securities		171,863,065		174,802,232
Other securities		1,365,794		1,726,849
	$	599,289,459	$	605,545,374

	Amortized Cost		Fair Value
Securities held to maturity:
Municipal securities	$	57,540,331	$	57,327,912
Securities available for sale:
U.S. govt. sponsored agency securities		370,595,745		371,574,015
Municipal securities		13,494,268		14,270,490
	$	384,090,013	$	385,844,505