Note 2 - Investment Securities (Tables)

3 Months Ended

Mar. 31, 2014

Investment Holdings [Abstract]

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

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Fair Value
March 31, 2014
Securities held to maturity:
Municipal securities	$	160,579,152	$	756,828	$	(4,768,120	)	$	156,567,860
Other securities		1,050,000		-		-			1,050,000
	$	161,629,152	$	756,828	$	(4,768,120	)	$	157,617,860
Securities available for sale:
U.S. govt. sponsored agency securities	$	363,901,863	$	31,503	$	(13,595,807	)	$	350,337,559
Residential mortgage-backed and related securities		159,343,903		1,377,020		(2,601,522	)		158,119,401
Municipal securities		34,495,776		997,316		(417,026	)		35,076,066
Other securities		1,378,550		565,961		-			1,944,511
	$	559,120,092	$	2,971,800	$	(16,614,355	)	$	545,477,537
December 31, 2013:
Securities held to maturity:
Municipal securities	$	144,401,895	$	299,789	$	(7,111,579	)	$	137,590,105
Other securities		1,050,000		-		-			1,050,000
	$	145,451,895	$	299,789	$	(7,111,579	)	$	138,640,105
Securities available for sale:
U.S. govt. sponsored agency securities	$	376,574,132	$	41,696	$	(20,142,841	)	$	356,472,987
Residential mortgage-backed and related securities		160,110,199		1,153,409		(3,834,157	)		157,429,451
Municipal securities		35,813,866		923,315		(778,324	)		35,958,857
Other securities		1,372,365		524,798		-			1,897,163
	$	573,870,562	$	2,643,218	$	(24,755,322	)	$	551,758,458

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, 2014:
Securities held to maturity:
Municipal securities	$	90,268,363	$	(3,972,217	)	$	11,141,166	$	(795,903	)	$	101,409,529	$	(4,768,120	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	330,406,007	$	(12,809,546	)	$	11,194,076	$	(786,261	)	$	341,600,083	$	(13,595,807	)
Residential mortgage-backed and related securities		74,273,019		(1,586,915	)		21,330,340		(1,014,607	)		95,603,359		(2,601,522	)
Municipal securities		12,715,294		(372,659	)		1,699,797		(44,367	)		14,415,091		(417,026	)
	$	417,394,320	$	(14,769,120	)	$	34,224,213	$	(1,845,235	)	$	451,618,533	$	(16,614,355	)
December 31, 2013:
Securities held to maturity:
Municipal securities	$	101,983,602	$	(6,711,240	)	$	2,697,375	$	(400,339	)	$	104,680,977	$	(7,111,579	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	333,194,820	$	(19,141,077	)	$	10,978,390	$	(1,001,764	)	$	344,173,210	$	(20,142,841	)
Residential mortgage-backed and related securities		94,723,092		(2,947,770	)		14,117,719		(886,387	)		108,840,811		(3,834,157	)
Municipal securities		13,890,692		(724,939	)		985,687		(53,385	)		14,876,379		(778,324	)
	$	441,808,604	$	(22,813,786	)	$	26,081,796	$	(1,941,536	)	$	467,890,400	$	(24,755,322	)

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

	Three Months Ended
	March 31, 2014		March 31, 2013
Proceeds from sales of securities	$	7,020,625	$	-
Pre-tax gross gains from sales of securities		20,625		-

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Securities held to maturity:
Due in one year or less	$	2,298,028	$	2,299,876
Due after one year through five years		10,898,311		10,876,493
Due after one year through five years		148,432,813		144,441,491
	$	161,629,152	$	157,617,860
Securities available for sale:
Due in one year or less	$	5,399,927	$	5,412,462
Due after one year through five years		51,172,655		50,810,680
Due after five years		341,825,057		329,190,483
	$	398,397,639	$	385,413,625
Residential mortgage-backed and related securities		159,343,903		158,119,401
Other securities		1,378,550		1,944,511
	$	559,120,092	$	545,477,537

	Amortized Cost		Fair Value
Securities held to maturity:
Municipal securities	$	107,791,951	$	104,916,513
Securities available for sale:
U.S. govt. sponsored agency securities		307,435,005		295,518,088
Municipal securities		22,063,064		22,190,224
	$	329,498,069	$	317,708,312