Note 4 - Loans Leases Receivable - Troubled Debt Restructurings (Details)	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of Loans / Leases	35	29
Pre-Modification Recorded Investment	$ 2,752,344	$ 7,880,881
Post-Modification Recorded Investment	2,752,344	7,880,881
Specific Allowance	$ 62,596	$ 1,225,716
Extended Maturity [Member]
Number of Loans / Leases	3	8
Pre-Modification Recorded Investment	$ 115,236	$ 935,221
Post-Modification Recorded Investment	115,236	935,221
Specific Allowance		$ 286,735
Payment Deferral [Member]
Number of Loans / Leases	32	20
Pre-Modification Recorded Investment	$ 2,637,108	$ 5,711,920
Post-Modification Recorded Investment	2,637,108	5,711,920
Specific Allowance	$ 62,596	$ 938,981
Interest Rate Below Market Reduction [Member]
Number of Loans / Leases		1
Pre-Modification Recorded Investment		$ 1,233,740
Post-Modification Recorded Investment		1,233,740
Specific Allowance
Finance Leases Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases	3	4
Pre-Modification Recorded Investment	$ 115,236	$ 410,653
Post-Modification Recorded Investment	115,236	410,653
Specific Allowance		$ 38,476
Finance Leases Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	24	13
Pre-Modification Recorded Investment	$ 1,703,255	$ 1,149,493
Post-Modification Recorded Investment	1,703,255	1,149,493
Specific Allowance		$ 125,940
Commercial Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases		3
Pre-Modification Recorded Investment		$ 247,476
Post-Modification Recorded Investment		247,476
Specific Allowance		$ 60,767
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	7	7
Pre-Modification Recorded Investment	$ 826,531	$ 4,562,427
Post-Modification Recorded Investment	826,531	4,562,427
Specific Allowance	$ 62,596	$ 813,041
Residential Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases		1
Pre-Modification Recorded Investment		$ 277,092
Post-Modification Recorded Investment		277,092
Specific Allowance		$ 187,492
Commercial Real Estate Portfolio Segment [Member] \| Payment Deferral [Member] \| Owner Occupied Commercial Real Estate Loans [Member]
Number of Loans / Leases	1
Pre-Modification Recorded Investment	$ 107,322
Post-Modification Recorded Investment	107,322
Specific Allowance
Commercial Real Estate Portfolio Segment [Member] \| Interest Rate Below Market Reduction [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Number of Loans / Leases		1
Pre-Modification Recorded Investment		$ 1,233,740
Post-Modification Recorded Investment		1,233,740
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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

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+ References

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- Definition

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+ References

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