Note 5 - Allowance for Credit Losses - Historical Loss on Unfunded Commitments (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Balance	$ 8,202,710	$ 7,809,700	$ 7,873,790
Provisions for credit losses	945,436	846,457	1,125,407
Loans charged off	(344,888)	(702,557)	(1,316,082)
Recoveries	181,537	249,110	126,585
Balance	8,984,795	8,202,710	7,809,700
Allowance for Loan and Lease Losses [Member]
Balance	7,866,523	7,519,970	7,609,467
Provisions for credit losses	970,000	800,000	1,100,000
Loans charged off	(344,888)	(702,557)	(1,316,082)
Recoveries	181,537	249,110	126,585
Balance	8,673,172	7,866,523	7,519,970
Allowance for Unfunded Commitments [Member]
Balance	336,187	289,730	264,323
Provisions for credit losses	(24,564)	46,457	25,407
Loans charged off
Recoveries
Balance	$ 311,623	$ 336,187	$ 289,730

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

+ Details

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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