Note 8 - Deposits - Interest Expense on Deposits (Details) - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Money market	$ 74,101	$ 64,011
Savings	18,585	20,141
Certificates of deposit	854,250	723,865
Interest bearing checking	16,306	12,299
	$ 963,242	$ 820,316

Aggregate amount of all interest expense on domestic deposit liabilities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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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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- Definition

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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