Note 8 - Deposits and Borrowed Funds - Short-term Borrowed Funds (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Collateral Carrying Value	$ 226,230	$ 237,537
Short-term borrowed funds	68,894	58,471
US Government-sponsored Enterprises Debt Securities [Member]
Collateral Carrying Value	72,771	74,173
Agency Residential MBS [Member]
Collateral Carrying Value	61,555	58,251
Corporate Debt Securities [Member]
Collateral Carrying Value	$ 91,904	$ 105,113

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant