Note 2 - Investment Securities (Tables)

9 Months Ended

Sep. 30, 2014

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, 2014
Securities held to maturity:
Municipal securities	$	184,790,139	$	1,861,338	$	(1,765,426	)	$	184,886,051
Other securities		1,050,000		-		-			1,050,000
	$	185,840,139	$	1,861,338	$	(1,765,426	)	$	185,936,051
Securities available for sale:
U.S. govt. sponsored agency securities	$	315,019,934	$	30,913	$	(9,046,242	)	$	306,004,605
Residential mortgage-backed and related securities		127,822,284		1,372,274		(1,414,809	)		127,779,749
Municipal securities		30,209,955		1,149,656		(99,465	)		31,260,146
Other securities		1,354,116		545,951		-			1,900,067
	$	474,406,289	$	3,098,794	$	(10,560,516	)	$	466,944,567
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
			Gross					Gross					Gross
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Losses			Value		Losses			Value		Losses
September 30, 2014:
Securities held to maturity:
Municipal securities	$	29,794,026	$	(633,024	)	$	43,172,941	$	(1,132,402	)	$	72,966,967	$	(1,765,426	)
Securities available for sale:
U.S. govt. sponsored agency securities	$	32,208,945	$	(156,930	)	$	262,773,625	$	(8,889,312	)	$	294,982,570	$	(9,046,242	)
Residential mortgage-backed and related securities		10,125,288		(74,264	)		58,008,272		(1,340,545	)		68,133,560		(1,414,809	)
Municipal securities		1,446,532		(3,113	)		5,616,381		(96,352	)		7,062,913		(99,465	)
	$	43,780,765	$	(234,307	)	$	326,398,278	$	(10,326,209	)	$	370,179,043	$	(10,560,516	)
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						Nine Months Ended
	September 30, 2014			September 30, 2013			September 30, 2014			September 30, 2013
Proceeds from sales of securities	$	39,876,889		$	31,225,516		$	65,754,467		$	37,393,047
Pre-tax gross gains from sales of securities		357,934			506,611			379,130			523,071
Pre-tax gross losses from sales of securities		(338,505	)		(89,675	)		(338,505	)		(89,675	)

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Securities held to maturity:
Due in one year or less	$	12,682,406	$	12,683,453
Due after one year through five years		16,825,667		16,856,667
Due after five years		156,332,066		156,395,931
	$	185,840,139	$	185,936,051
Securities available for sale:
Due in one year or less	$	3,649,998	$	3,664,418
Due after one year through five years		60,972,541		60,242,076
Due after five years		280,607,350		273,358,257
	$	345,229,889	$	337,264,751
Residential mortgage-backed and related securities		127,822,284		127,779,749
Other securities		1,354,116		1,900,067
	$	474,406,289	$	466,944,567

	Amortized Cost		Fair Value
Securities held to maturity:
Municipal securities	$	99,883,698	$	100,074,857
Securities available for sale:
U.S. govt. sponsored agency securities		250,617,040		243,092,527
Municipal securities		18,473,306		18,985,950
	$	269,090,346	$	262,078,477

Bonds [Member]

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

Schedule of Debt [Table Text Block]

September 30, 2014:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Illinois		32	$	23,058,258	$	23,431,499	$	732,234
Iowa		25		16,557,625		16,746,965		669,879
Missouri		12		6,136,797		6,097,169		508,097
Other		52		16,674,720		16,908,510		325,164
Total general obligation bonds		121	$	62,427,400	$	63,184,143	$	522,183

December 31, 2013:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Iowa		30	$	17,946,059	$	17,444,045	$	581,468
Illinois		36		15,063,325		15,264,718		424,020
Other		67		22,166,026		21,512,582		321,083
Total general obligation bonds		133	$	55,175,410	$	54,221,345	$	407,679

September 30, 2014:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Iowa		37	$	59,955,899	$	60,603,053	$	1,637,920
Missouri		65		54,016,464		53,997,386		830,729
Indiana		12		17,991,200		17,835,277		1,486,273
Kansas		6		12,310,134		12,139,318		2,023,220
Other		31		8,298,997		8,387,020		270,549
Total revenue bonds		151	$	152,572,694	$	152,962,054	$	1,012,994

December 31, 2013:
U.S. State:	Number of Issuers		Amortized Cost		Fair Value		Average Exposure Per Issuer (Fair Value)
Iowa		31	$	47,903,572	$	46,257,997	$	1,492,193
Missouri		57		42,085,249		40,054,613		702,713
Indiana		8		15,020,000		14,324,717		1,790,590
Kansas		5		11,022,382		9,997,068		1,999,414
Other		35		9,009,148		8,693,222		248,378
Total revenue bonds		136	$	125,040,351	$	119,327,617	$	877,409