Note 10 - Fair Value Measurements - Estimated Fair Values of the Company's Financial Information (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Available-for-sale debt securities	$ 274,114	$ 296,032
Equity securities, at fair value	903	891
Reported Value Measurement [Member]
Available-for-sale debt securities	274,114	296,032
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and short term investments	32,745	36,481
Equity securities, at fair value	903	891
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Restricted stock	3,120	3,123
Loans held for sale	609	820
Accrued interest receivable	3,706	3,614
Deposits	1,040,090	1,095,629
Borrowed funds	39,298	34,240
Accrued interest payable	339	338
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans, net	829,611	829,581
Equity securities without readily determinable fair values	1,658	1,658
Servicing rights	350	350
Estimate of Fair Value Measurement [Member]
Available-for-sale debt securities	274,114	296,032
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and short term investments	32,745	36,481
Equity securities, at fair value	903	891
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Restricted stock	3,120	3,123
Loans held for sale	609	820
Accrued interest receivable	3,706	3,614
Deposits	1,038,922	1,093,797
Borrowed funds	39,267	34,108
Accrued interest payable	339	338
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans, net	817,729	816,234
Equity securities without readily determinable fair values	1,658	1,658
Servicing rights	$ 836	$ 878

The fair value portion of liabilities related to accrued interest on debt.

No definition available.

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- Definition

The fair value of interest earned but not received.

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No definition available.

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- Definition

The fair value of the rights retained or purchased to service mortgages.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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Amount of restricted investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
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Amount of investment in equity security without readily determinable fair value.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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