Note 8 - Deposits and Borrowed Funds (Details Textual) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Demand Deposit Overdrafts	$ 918		$ 918		$ 2,786
Interest Expense, Time Deposits, $100,000 or More	$ 95	$ 105	$ 192	$ 211

Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices.

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=114873765&loc=SL114874048-224260

Name:	us-gaap_InterestExpenseTimeDeposits100000OrMore
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration