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Note 3 - Loans and Allowance for Loan Losses - Age Analysis of Past Due Loans (Details) - USD ($)		Sep. 30, 2021	Dec. 31, 2020
Loans and Leases Receivable, Net of Deferred Income, Total		$ 3,313,709,000	$ 3,193,470,000
Loans past due 90 days or more still accruing interest		0	0
Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		2,842,359,000	2,793,962,000
Loans past due 90 days or more still accruing interest		0	0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	[1]	1,074,394,000	1,145,423,000
Loans past due 90 days or more still accruing interest		0	0
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		38,380,000	55,055,000
Loans past due 90 days or more still accruing interest		0	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		551,762,000	529,953,000
Loans past due 90 days or more still accruing interest		0	0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		998,697,000	917,436,000
Loans past due 90 days or more still accruing interest		0	0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		179,126,000	146,095,000
Loans past due 90 days or more still accruing interest		0	0
Retail Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		471,350,000	399,508,000
Loans past due 90 days or more still accruing interest		0	0
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		59,732,000	61,620,000
Loans past due 90 days or more still accruing interest		0	0
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		411,618,000	337,888,000
Loans past due 90 days or more still accruing interest		0	0
Financial Asset, 30 to 59 Days Past Due [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		418,000	1,520,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	261,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	261,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		418,000	1,259,000
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		103,000	112,000
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		315,000	1,147,000
Financial Asset, 60 to 89 Days Past Due [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		374,000	681,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	369,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	172,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	197,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		374,000	312,000
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		11,000	65,000
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		363,000	247,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		303,000	840,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		44,000	444,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		44,000	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	421,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	23,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		259,000	396,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		35,000	54,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		224,000	342,000
Financial Asset, Past Due [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		1,095,000	3,041,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		44,000	1,074,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		44,000	433,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	618,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	23,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		0	0
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		1,051,000	1,967,000
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		149,000	231,000
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		902,000	1,736,000
Financial Asset, Not Past Due [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		3,312,614,000	3,190,429,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		2,842,315,000	2,792,888,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		1,074,350,000	1,144,990,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		38,380,000	55,055,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		551,762,000	529,335,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		998,697,000	917,413,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		179,126,000	146,095,000
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		470,299,000	397,541,000
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		59,583,000	61,389,000
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans and Leases Receivable, Net of Deferred Income, Total		$ 410,716,000	$ 336,152,000
[1] Includes $116 million and $365 million in loans originated under the Paycheck Protection Program for September 30, 2021 and December 31, 2020, respectively.

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Amount of financing receivable 90 days or more past due and still accruing.

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