Note 8 - Deposits - Interest Expense on Deposits (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Money market	$ 60,802	$ 75,107
Savings	18,742	18,854
Certificates of deposit	2,252,016	1,483,780
Interest bearing checking	491,115	184,372
	$ 2,822,675	$ 1,762,113

Aggregate amount of all interest expense on domestic deposit liabilities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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- Definition

Amount of interest expense on domestic certificates of deposit liabilities.

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- Definition

Amount of interest expense on domestic checking deposit liabilities.

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Amount of interest expense on domestic savings deposit liabilities.

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- Definition

Interest expense incurred on all money market deposits.

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