Note 8 - Fair Value of Financial Instruments - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Financial Assets:
Securities	$ 304,122	$ 309,516
Other Equity Securities	8,508	9,282
Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Securities
Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Securities	296,083	301,132
Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Securities	8,039	8,384
Reported Value Measurement [Member]
Financial Assets:
Cash and Short-Term Investments	82,699	137,908
Securities	304,122	309,516
Mortgage Loans Held for Sale	753	58
Loans - Net	1,574,364	1,517,249
Cash Value of BOLI	32,050	31,882
Other Equity Securities	8,508	9,282
Total	2,002,496	2,005,895
Financial Liabilities:
Deposits	1,744,383	1,733,934
Borrowings	66,070	92,229
Total	1,810,453	1,826,163
Estimate of Fair Value Measurement [Member]
Financial Assets:
Cash and Short-Term Investments	82,699	137,908
Securities	304,122	309,516
Mortgage Loans Held for Sale	753	58
Loans - Net	1,554,947	1,495,454
Cash Value of BOLI	32,050	31,882
Other Equity Securities	8,508	9,282
Total	1,983,079	1,984,100
Financial Liabilities:
Deposits	1,736,715	1,717,698
Borrowings	80,116	104,930
Total	1,816,831	1,822,628
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Cash and Short-Term Investments	82,699	137,908
Securities
Mortgage Loans Held for Sale
Loans - Net
Cash Value of BOLI
Other Equity Securities
Total	82,699	137,908
Financial Liabilities:
Deposits
Borrowings
Total
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Cash and Short-Term Investments
Securities	296,083	301,132
Mortgage Loans Held for Sale	753	58
Loans - Net
Cash Value of BOLI	32,050	31,882
Other Equity Securities
Total	328,886	333,072
Financial Liabilities:
Deposits
Borrowings	80,116	104,930
Total	80,116	104,930
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Cash and Short-Term Investments
Securities	8,039	8,384
Mortgage Loans Held for Sale
Loans - Net	1,554,947	1,495,454
Cash Value of BOLI
Other Equity Securities	8,508	9,282
Total	1,571,494	1,513,120
Financial Liabilities:
Deposits	1,736,715	1,717,698
Borrowings
Total	$ 1,736,715	$ 1,717,698

Represents the fair value portion of other equity securities.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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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.

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- Definition

Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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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.

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- References

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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- Definition

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

Fair value portion of mortgage loans held-for-sale.

+ References

No definition available.

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