Note 9 - Short-term Borrowings - Overnight Repurchase Agreement Collateralized Investment Securities (Details) - Securities Sold under Agreements to Repurchase [Member] - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Securities sold under repurchase agreements	$ 24,316,340	$ 20,893,982
Less: overcollateralized position	22,232,183	13,890,860
Assets sold	2,084,157	7,003,122
US Government Agencies Debt Securities
Securities sold under repurchase agreements	3,661,995	2,077,702
Residential Mortgage Backed Securities
Securities sold under repurchase agreements	$ 20,654,345	$ 18,816,280

Amount of overcapitalized position that is intend to cover any minor interest rate movement.

No definition available.

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- Definition

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Details

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- Details

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- Details

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