Note 13 - Related Parties - Loans Outstanding to Directors and Executive Officers (Details) - Directors and Executive Officers [Member] - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Beginning balance	$ 8,882,000	$ 11,151,000
New loans	6,374,000	4,652,000
Repayments	(783,000)	(6,921,000)
Ending balance	$ 14,473,000	$ 8,882,000

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(e))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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- Definition

Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

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