Note 5 - Fair Value - Assets Measured At Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
AFS	$ 259,644,940	$ 272,907,907
US Government Agencies Debt Securities [Member]
AFS	36,867,510	38,096,534
Residential Mortgage Backed Securities [Member]
AFS	157,289,043	163,301,304
US States and Political Subdivisions Debt Securities [Member]
AFS	61,201,804	66,625,496
Other Securities [Member]
AFS	4,286,583	4,884,573
Fair Value, Measurements, Nonrecurring [Member]
Assets Fair Value	19,334,785	23,615,310
Impaired loans/leases	5,564,760	8,972,337
OREO	13,770,025	14,642,973
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets Fair Value
Impaired loans/leases
OREO
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets Fair Value
Impaired loans/leases
OREO
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets Fair Value	19,334,785	23,615,310
Impaired loans/leases	5,564,760	8,972,337
OREO	13,770,025	14,642,973
Fair Value, Measurements, Recurring [Member]
Assets Fair Value	264,802,436	277,811,845
Liabilities Fair Value	4,500,318	4,397,238
Fair Value, Measurements, Recurring [Member] \| Interest Rate Cap [Member]
Interest rate caps	657,178	506,700
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate caps	4,500,318	4,397,238
Derivative Liabilites	4,500,318	4,397,238
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets Fair Value		1,028
Liabilities Fair Value
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Cap [Member]
Interest rate caps
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Interest rate caps
Derivative Liabilites
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets Fair Value	264,802,436	277,810,817
Liabilities Fair Value	4,500,318	4,397,238
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Cap [Member]
Interest rate caps	657,178	506,700
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Interest rate caps	4,500,318	4,397,238
Derivative Liabilites	4,500,318	4,397,238
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets Fair Value
Liabilities Fair Value
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Cap [Member]
Interest rate caps
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Interest rate caps
Derivative Liabilites
Fair Value, Measurements, Recurring [Member] \| US Government Agencies Debt Securities [Member]
AFS	36,867,510	38,096,534
Fair Value, Measurements, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
AFS
Fair Value, Measurements, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
AFS	36,867,510	38,096,534
Fair Value, Measurements, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
AFS
Fair Value, Measurements, Recurring [Member] \| Residential Mortgage Backed Securities [Member]
AFS	157,289,043	163,301,304
Fair Value, Measurements, Recurring [Member] \| Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
AFS
Fair Value, Measurements, Recurring [Member] \| Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
AFS	157,289,043	163,301,304
Fair Value, Measurements, Recurring [Member] \| Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
AFS
Fair Value, Measurements, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
AFS	61,201,804	66,625,496
Fair Value, Measurements, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
AFS
Fair Value, Measurements, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
AFS	61,201,804	66,625,496
Fair Value, Measurements, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
AFS
Fair Value, Measurements, Recurring [Member] \| Other Securities [Member]
AFS	4,286,583	4,884,573
Fair Value, Measurements, Recurring [Member] \| Other Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
AFS		1,028
Fair Value, Measurements, Recurring [Member] \| Other Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
AFS	4,286,583	4,883,545
Fair Value, Measurements, Recurring [Member] \| Other Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
AFS

The fair value of impaired loans.

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- Definition

The fair value of other real estate owned.

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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-Topic 210
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-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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-Publisher FASB
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-Topic 210
-SubTopic 20
-Section 55
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-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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