Note 3 - Loans Leases Receivable - Troubled Debt Restructurings (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Number of Loans / Leases	8	2	36	13
Pre-Modification Recorded Investment	$ 1,037,049	$ 461,643	$ 2,795,032	$ 2,530,491
Post-Modification Recorded Investment	1,037,049	461,643	2,795,032	2,530,491
Specific Allowance
Extended Maturity [Member]
Number of Loans / Leases	8	2	2	5
Pre-Modification Recorded Investment	$ 1,037,049	$ 461,643	$ 104,382	$ 462,939
Post-Modification Recorded Investment	1,037,049	461,643	104,382	462,939
Specific Allowance
Payment Deferral [Member]
Number of Loans / Leases			34	7
Pre-Modification Recorded Investment			$ 2,690,650	$ 833,812
Post-Modification Recorded Investment			2,690,650	833,812
Specific Allowance
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
Commercial Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases	4			1
Pre-Modification Recorded Investment	$ 620,452			$ 52,286
Post-Modification Recorded Investment	620,452			52,286
Specific Allowance
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases			7	1
Pre-Modification Recorded Investment			$ 801,650	$ 62,140
Post-Modification Recorded Investment			801,650	62,140
Specific Allowance
Commercial Portfolio Segment [Member] \| 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	4	2	2	4
Pre-Modification Recorded Investment	$ 416,597	$ 461,643	$ 104,382	$ 410,653
Post-Modification Recorded Investment	416,597	461,643	104,382	410,653
Specific Allowance
Finance Leases Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases			27	6
Pre-Modification Recorded Investment			$ 1,889,000	$ 771,672
Post-Modification Recorded Investment			1,889,000	771,672
Specific Allowance

Specific allowance of amount of investment in financing receivables modified by troubled debt restructurings.

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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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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

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+ References

+ Details

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