Note 3 - Loans Leases Receivable - Troubled Debt Restructurings (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) item	Jun. 30, 2018 USD ($) lease	Jun. 30, 2017 USD ($) lease
Number of Loans / Leases	17	3	28
Pre-Modification Recorded Investment	$ 948,170	$ 93,844	$ 1,757,983
Post-Modification Recorded Investment	$ 948,170	$ 93,844	$ 1,757,983
Extended Maturity [Member]
Number of Loans / Leases	1		2
Pre-Modification Recorded Investment	$ 98,119		$ 104,382,000
Post-Modification Recorded Investment	$ 98,119		$ 104,382,000
Payment Deferral [Member]
Number of Loans / Leases	16	3	26
Pre-Modification Recorded Investment	$ 850,051	$ 93,844	$ 1,653,601
Post-Modification Recorded Investment	$ 850,051	$ 93,844	$ 1,653,601
Finance Leases Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases	1		2
Pre-Modification Recorded Investment	$ 98,119		$ 104,382
Post-Modification Recorded Investment	$ 98,119		$ 104,382
Finance Leases Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	15	2	23
Pre-Modification Recorded Investment	$ 802,542	$ 47,524	$ 1,472,403
Post-Modification Recorded Investment	$ 802,542	$ 47,524	$ 1,472,403
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	1		3
Pre-Modification Recorded Investment	$ 47,509		$ 181,198
Post-Modification Recorded Investment	$ 47,509		$ 181,198
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases \| lease		1
Pre-Modification Recorded Investment		$ 46,320
Post-Modification Recorded Investment		$ 46,320

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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