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Note 3 - Loans and Allowance for Loan Losses - Components of Loan Portfolio (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Loans	$ 2,901,543,000	$ 2,856,667,000
Percent of portfolio	100.00%	100.00%
Period increase (decrease)	1.60%
Commercial Portfolio Segment [Member]
Loans	$ 2,472,330,000	$ 2,441,544,000
Percent of portfolio	85.20%	85.50%
Period increase (decrease)	1.30%
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans	$ 873,679,000	$ 846,551,000
Percent of portfolio	30.10%	29.60%
Period increase (decrease)	3.20%
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans	$ 62,908,000	$ 56,119,000
Percent of portfolio	2.20%	2.00%
Period increase (decrease)	12.10%
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans	$ 579,229,000	$ 579,003,000
Percent of portfolio	20.00%	20.30%
Period increase (decrease)	0.10%
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans	$ 823,366,000	$ 835,346,000
Percent of portfolio	28.30%	29.20%
Period increase (decrease)	(1.40%)
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans	$ 133,148,000	$ 124,525,000
Percent of portfolio	4.60%	4.40%
Period increase (decrease)	6.90%
Retail Portfolio Segment [Member]
Loans	$ 429,213,000	$ 415,123,000
Percent of portfolio	14.80%	14.50%
Period increase (decrease)	3.40%
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans	$ 72,875,000	$ 75,374,000
Percent of portfolio	2.50%	2.60%
Period increase (decrease)	(3.30%)
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans	$ 356,338,000	$ 339,749,000
Percent of portfolio	12.30%	11.90%
Period increase (decrease)	4.90%

X

- Definition

Loan portfolio classes and segments expressed as a percentage of the companies aggregate loans.

+ References

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- Definition

The percentage of increase or (decrease) during the period in loans and leases receivable net of deferred income.

+ References

No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524

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