Note 7 - Deposits - Interest Expense on Deposits (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
NOW and Money Market accounts	$ 1,235,359	$ 1,276,808	$ 1,242,158
Savings accounts	55,094	49,467	49,071
Certificate accounts	1,002,872	1,102,928	1,050,081
Early withdrawal penalties	(9,343)	(5,332)	(12,220)
	$ 2,283,982	$ 2,423,871	$ 2,329,090

Aggregate amount of interest expense on all deposits.

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

Early withdrawal penalties on domestic deposits which discourage customer withdrawal prior to maturity.

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- Definition

Interest expense incurred on all money market deposits.

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Interest expense incurred on all savings account deposits.

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- Definition

The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

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