Note 9 - Revenue Recognition - Noninterest Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Noninterest Income (in-scope of Topic 606)	$ 1,484	$ 1,540
Noninterest Income (out-of-scope of Topic 606)	1,005	483
Total noninterest income	2,489	2,023
Deposit Account [Member]
Noninterest Income (in-scope of Topic 606)	590	670
Product and Service, Other [Member]
Noninterest Income (in-scope of Topic 606)	52	33
Credit and Debit Card [Member]
Noninterest Income (in-scope of Topic 606)	309	344
Fiduciary and Trust [Member]
Noninterest Income (in-scope of Topic 606)	397	402
Insurance and Investment [Member]
Noninterest Income (in-scope of Topic 606)	$ 136	$ 91

Amount, including tax collected from customer, of revenue (outside of topic 606) from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

No definition available.

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- Definition

The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

+ References

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 210.9-04.13)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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