Note 2 - Investment Securities (Tables)

3 Months Ended

Mar. 31, 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
March 31, 2015
Securities held to maturity:
Municipal securities	$	214,096,171	$	2,303,569	$	(1,812,743	)	$	214,586,997
Other securities		1,050,000		-		-			1,050,000
	$	215,146,171	$	2,303,569	$	(1,812,743	)	$	215,636,997
Securities available for sale:
U.S. govt. sponsored agency securities	$	300,131,663	$	444,159	$	(1,395,567	)	$	299,180,255
Residential mortgage-backed and related securities		90,632,701		1,192,895		(462,296	)		91,363,300
Municipal securities		28,649,282		1,107,755		(43,723	)		29,713,314
Other securities		1,370,532		630,797		(98	)		2,001,231
	$	420,784,178	$	3,375,606	$	(1,901,684	)	$	422,258,100
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
March 31, 2015:
Securities held to maturity:
Municipal securities	$	48,692,267	$	(991,314	)	$	30,617,292	$	(821,429	)	$	79,309,559	$	(1,812,743	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	102,286,952	$	(435,457	)	$	93,948,175	$	(960,110	)	$	196,235,127	$	(1,395,567	)
Residential mortgage-backed and related securities		27,194,344		(126,489	)		22,421,887		(335,807	)		49,616,231		(462,296	)
Municipal securities		598,285		(2,790	)		1,339,977		(40,933	)		1,938,262		(43,723	)
Other securities		476		(98	)		-		-			476		(98	)
	$	130,080,057	$	(564,834	)	$	117,710,039	$	(1,336,850	)	$	247,790,096	$	(1,901,684	)
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
	March 31, 2015			March 31, 2014
Proceeds from sales of securities	$	54,971,056		$	7,020,625
Pre-tax gross gains from sales of securities		573,684			20,625
Pre-tax gross losses from sales of securities		(152,618	)		-

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Securities held to maturity:
Due in one year or less	$	3,866,598	$	3,871,276
Due after one year through five years		18,512,988		18,595,028
Due after five years		192,766,585		193,170,693
	$	215,146,171	$	215,636,997
Securities available for sale:
Due in one year or less	$	34,982,411	$	34,994,562
Due after one year through five years		104,102,115		104,066,092
Due after five years		189,696,419		189,832,915
	$	328,780,945	$	328,893,569
Residential mortgage-backed and related securities		90,632,701		91,363,300
Other securities		1,370,532		2,001,231
	$	420,784,178	$	422,258,100

	Amortized Cost		Fair Value
Securities held to maturity:
Municipal securities	$	127,760,995	$	128,323,293
Securities available for sale:
U.S. govt. sponsored agency securities		185,507,330		184,490,370
Municipal securities		17,800,256		18,353,901
	$	203,307,586	$	202,844,271

Bonds [Member]

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

Schedule of Debt [Table Text Block]

U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Iowa		15	$	21,431,325	$	21,602,520	$	1,440,168
Missouri		11		7,091,686		7,085,546		644,141
Illinois		9		11,925,483		12,255,809		1,361,757
Other		35		14,918,372		15,295,418		437,012
Total general obligation bonds		70	$	55,366,866	$	56,239,293	$	803,418

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
Missouri		11		8,424,928		8,426,047		766,004
Illinois		10		22,447,799		22,784,638		2,278,464
Other		42		16,838,719		17,110,831		407,401
Total general obligation bonds		77	$	67,868,415	$	68,768,171	$	893,093

U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Missouri		35	$	66,627,817	$	66,749,366	$	1,907,125
Iowa		25		73,326,036		73,890,396		2,955,616
Indiana		11		25,563,200		25,397,220		2,308,838
Kansas		3		12,120,688		12,100,898		4,033,633
Other		10		9,740,846		9,923,138		992,314
Total revenue bonds		84	$	187,378,587	$	188,061,018	$	2,238,822

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