Note 3 - Loans and Allowance for Loan Losses - Loans by Credit Quality Indicators (Details) - USD ($)		Dec. 31, 2020		Dec. 31, 2019	Dec. 31, 2018
Loans		$ 3,216,358,000		$ 2,856,667,000	$ 2,753,085,000
Commercial Portfolio Segment [Member]
Loans		2,793,962,000		2,441,544,000	$ 2,360,106,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans	[1]	1,145,423,000		846,551,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans		55,055,000		56,119,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans		529,953,000		579,003,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans		917,436,000		835,346,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans		146,095,000		124,525,000
Grades 1-4 [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans		828,706,000	[2]	521,920,000
Grades 1-4 [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans		22,547,000	[2]	26,065,000
Grades 1-4 [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans		315,134,000	[2]	351,671,000
Grades 1-4 [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans		396,700,000	[2]	563,087,000
Grades 1-4 [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans		91,711,000	[2]	85,152,000
Grades 5-7 [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans		306,614,000		309,824,000
Grades 5-7 [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans		32,398,000		29,716,000
Grades 5-7 [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans		185,541,000		220,980,000
Grades 5-7 [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans		520,395,000		272,124,000
Grades 5-7 [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans		54,111,000		39,203,000
Grades 8-9 [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans		10,103,000		14,807,000
Grades 8-9 [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans		110,000		338,000
Grades 8-9 [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans		29,278,000		6,352,000
Grades 8-9 [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans		341,000		135,000
Grades 8-9 [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans		$ 273,000		$ 170,000

[1] For December 31, 2020, includes $365 million in loans originated under the Paycheck Protection Program.

[2] Included in Commercial and Industrial Loans Grades 1 – 4 are $365 million of loans originated under the Paycheck Protection Program.