Note 2 - Investment Securities (Tables)

9 Months Ended

Sep. 30, 2015

Note 2 - Investment Securities (Tables) [Line Items]

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

			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		(Losses)			Value
September 30, 2015
Securities held to maturity:
Municipal securities	$	237,590,598	$	2,429,898	$	(1,649,655	)	$	238,370,841
Other securities		1,050,000		-		-			1,050,000
	$	238,640,598	$	2,429,898	$	(1,649,655	)	$	239,420,841
Securities available for sale:
U.S. govt. sponsored agency securities	$	247,911,701	$	577,904	$	(865,014	)	$	247,624,591
Residential mortgage-backed and related securities		74,444,924		938,379		(481,744	)		74,901,559
Municipal securities		26,815,175		925,922		(39,445	)		27,701,652
Other securities		1,344,814		633,415		(71,680	)		1,906,549
	$	350,516,614	$	3,075,620	$	(1,457,883	)	$	352,134,351
December 31, 2014:
Securities held to maturity:
Municipal securities	$	198,829,574	$	2,420,298	$	(1,186,076	)	$	200,063,796
Other securities		1,050,000		-		-			1,050,000
	$	199,879,574	$	2,420,298	$	(1,186,076	)	$	201,113,796
Securities available for sale:
U.S. govt. sponsored agency securities	$	312,959,760	$	173,685	$	(5,263,873	)	$	307,869,572
Residential mortgage-backed and related securities		110,455,925		1,508,331		(541,032	)		111,423,224
Municipal securities		29,408,740		1,053,713		(62,472	)		30,399,981
Other securities		1,342,554		625,145		(846	)		1,966,853
	$	454,166,979	$	3,360,874	$	(5,868,223	)	$	451,659,630

Schedule of Unrealized Loss on Investments [Table Text Block]

	Less than 12 Months					12 Months or More					Total
			Gross					Gross					Gross
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Losses			Value		Losses			Value		Losses
September 30, 2015:
Securities held to maturity:
Municipal securities	$	53,289,140	$	(1,053,551	)	$	15,450,731	$	(596,104	)	$	68,739,871	$	(1,649,655	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	54,246,955	$	(229,249	)	$	74,289,108	$	(635,765	)	$	128,536,063	$	(865,014	)
Residential mortgage-backed and related securities		18,732,443		(126,214	)		20,731,733		(355,530	)		39,464,176		(481,744	)
Municipal securities		1,621,304		(11,388	)		852,734		(28,057	)		2,474,038		(39,445	)
Other securities		71,751		(71,680	)		-		-			71,751		(71,680	)
	$	74,672,453	$	(438,531	)	$	95,873,575	$	(1,019,352	)	$	170,546,028	$	(1,457,883	)
December 31, 2014:
Securities held to maturity:
Municipal securities	$	20,419,052	$	(587,992	)	$	38,779,545	$	(598,084	)	$	59,198,597	$	(1,186,076	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	23,970,085	$	(102,695	)	$	255,743,056	$	(5,161,178	)	$	279,713,141	$	(5,263,873	)
Residential mortgage-backed and related securities		10,710,671		(10,139	)		37,570,774		(530,893	)		48,281,445		(541,032	)
Municipal securities		920,935		(1,773	)		4,425,337		(60,699	)		5,346,272		(62,472	)
Other securities		243,004		(846	)		-		-			243,004		(846	)
	$	35,844,695	$	(115,453	)	$	297,739,167	$	(5,752,770	)	$	333,583,862	$	(5,868,223	)

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

	Three Months Ended						Nine Months Ended
	September 30, 2015			September 30, 2014			September 30, 2015			September 30, 2014
Proceeds from sales of securities	$	11,922,915		$	39,876,889		$	65,889,838		$	65,754,467
Pre-tax gross gains from sales of securities		102,766			357,934			672,317			379,130
Pre-tax gross losses from sales of securities		(46,186	)		(338,505	)		(198,804	)		(338,505	)

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Securities held to maturity:
Due in one year or less	$	4,391,209	$	4,396,637
Due after one year through five years		17,965,982		18,089,831
Due after five years		216,283,407		216,934,373
	$	238,640,598	$	239,420,841
Securities available for sale:
Due in one year or less	$	1,356,439	$	1,360,215
Due after one year through five years		120,148,336		120,643,573
Due after five years		153,222,101		153,322,455
	$	274,726,876	$	275,326,243
Residential mortgage-backed and related securities		74,444,924		74,901,559
Other securities		1,344,814		1,906,549
	$	350,516,614	$	352,134,351

	Amortized Cost		Fair Value
Securities held to maturity:
Municipal securities	$	131,904,972	$	132,612,402
Securities available for sale:
U.S. govt. sponsored agency securities		159,441,770		158,761,957
Municipal securities		16,774,804		17,200,807
	$	176,216,574	$	175,962,764

Schedule of Debt [Table Text Block]

	September 30, 2015		December 31, 2014
Wholesale structured repurchase agreements	$	115,000,000	$	130,000,000
Term note		-		17,625,000
Series A subordinated notes		-		2,657,492
	$	115,000,000	$	150,282,492

Bonds [Member]

Note 2 - Investment Securities (Tables) [Line Items]

Schedule of Debt [Table Text Block]

September 30, 2015:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Iowa		15	$	20,225,477	$	20,363,737	$	1,357,582
Illinois		10		11,851,955		12,191,238		1,219,124
Missouri		12		7,930,365		7,968,565		664,047
North Dakota		3		6,675,000		6,767,961		2,255,987
Other		41		17,122,829		17,398,100		424,344
Total general obligation bonds		81	$	63,805,626	$	64,689,601	$	798,637

December 31, 2014:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Iowa		14	$	20,156,969	$	20,446,655	$	1,460,475
Illinois		10		22,447,799		22,784,638		2,278,464
Missouri		11		8,424,928		8,426,047		766,004
Other		42		16,838,719		17,110,831		407,401
Total general obligation bonds		77	$	67,868,415	$	68,768,171	$	893,093

September 30, 2015:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Missouri		40	$	75,016,470	$	75,197,907	$	1,879,948
Iowa		26		71,365,816		71,890,381		2,765,015
Indiana		14		34,701,481		34,707,516		2,479,108
Kansas		3		11,751,560		11,688,179		3,896,060
Other		4		7,764,820		7,898,909		1,974,727
Total revenue bonds		87	$	200,600,147	$	201,382,892	$	2,314,746

December 31, 2014:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Missouri		30	$	62,358,276	$	62,584,516	$	2,086,151
Iowa		20		59,417,246		60,402,941		3,020,147
Indiana		8		17,991,200		17,925,721		2,240,715
Kansas		2		12,307,866		12,332,528		6,166,264
Other		4		8,295,311		8,449,900		2,112,475
Total revenue bonds		64	$	160,369,899	$	161,695,606	$	2,526,494