Note 6 - Fair Value (Tables)

3 Months Ended

Mar. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value Measurements, Recurring and Nonrecurring [Table Text Block]

			Fair Value Measurements at Reporting Date Using
			Quoted Prices		Significant
			in Active		Other		Significant
			Markets for		Observable		Unobservable
			Identical Assets		Inputs		Inputs
	Fair Value		(Level 1)		(Level 2)		(Level 3)
March 31, 2016:
Securities available for sale:
U.S. govt. sponsored agency securities	$	132,741,822	$	-	$	132,741,822	$	-
Residential mortgage-backed and related securities		116,452,374		-		116,452,374		-
Municipal securities		24,929,655		-		24,929,655		-
Other securities		2,064,016		779		2,063,237		-
Derivative instruments		450,651		-		450,651		-
	$	276,638,518	$	779	$	276,637,739	$	-
December 31, 2015:
Securities available for sale:
U.S. govt. sponsored agency securities	$	213,537,379	$	-	$	213,537,379	$	-
Residential mortgage-backed and related securities		80,670,135		-		80,670,135		-
Municipal securities		27,578,588		-		27,578,588		-
Other securities		1,648,880		411		1,648,469		-
Derivative instruments		856,024		-		856,024
	$	324,291,006	$	411	$	324,290,595	$	-

			Fair Value Measurements at Reporting Date Using
	Fair Value		Level 1		Level 2		Level 3
March 31, 2016:
Impaired loans/leases	$	4,969,221	$	-	$	-	$	4,969,221
OREO		7,214,706		-		-		7,214,706
	$	12,183,927	$	-	$	-	$	12,183,927
December 31, 2015:
Impaired loans/leases	$	4,545,966	$	-	$	-	$	4,545,966
OREO		7,722,711		-		-		7,722,711
	$	12,268,677	$	-	$	-	$	12,268,677

Fair Value Inputs, Assets, Quantitative Information [Table Text Block]

	Quantitave Information about Level Fair Value Measurments
	Fair Value March 31, 2016		Fair Value December 31, 2015		Valuation Technique	Unobservable Input	Range
Impaired loans/leases	$	4,969,221	$	4,545,966	Appraisal of collateral	Appraisal adjustments	-10.00%	to	-50.00%
OREO		7,214,706		7,722,711	Appraisal of collateral	Appraisal adjustments	0.00%	to	-35.00%

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Fair Value	As of March 31, 2016					As of December 31, 2015
	Hierarchy	Carrying		Estimated			Carrying		Estimated
	Level	Value		Fair Value			Value		Fair Value
Cash and due from banks	Level 1	$	44,930,836	$	44,930,836		$	41,742,321	$	41,742,321
Federal funds sold	Level 2		15,740,000		15,740,000			19,850,000		19,850,000
Interest-bearing deposits at financial institutions	Level 2		41,489,171		41,489,171			36,313,965		36,313,965
Investment securities:
Held to maturity	Level 2		261,129,586		264,414,722			253,674,159		255,691,285
Available for sale	See Previous Table		276,187,867		276,187,867			323,434,982		323,434,982
Loans/leases receivable, net	Level 3		4,601,131		4,969,221			4,209,228		4,545,966
Loans/leases receivable, net	Level 2		1,841,827,043		(4,601,131	)		1,767,672,541		1,764,178,772
Derivative instruments	Level 2		450,651		450,651			856,024		856,024
Deposits:
Nonmaturity deposits	Level 2		1,586,207,114		1,586,207,114			1,516,599,081		1,516,599,081
Time deposits	Level 2		403,365,975		404,278,000			364,067,103		364,192,000
Short-term borrowings	Level 2		64,022,811		64,022,811			144,662,716		144,662,716
FHLB advances	Level 2		150,500,000		152,206,000			151,000,000		153,143,000
Other borrowings	Level 2		100,000,000		106,466,000			110,000,000		116,061,000
Junior subordinated debentures	Level 2		33,378,402		24,520,003			38,499,052		27,642,093