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Note 3 - Loans and Allowance for Loan Losses - Age Analysis of Past Due Loans (Details) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Past due loans |  | $ 1,405,000 | $ 1,884,000
Current loans |  | 3,331,651,000 | 2,854,783,000
Loans |  | 3,333,056,000 | 2,856,667,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] |  |  |
Past due loans |  | 464,000 | 325,000
Current loans |  | 2,900,788,000 | 2,441,219,000
Loans |  | 2,901,252,000 | 2,441,544,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Past due loans |  | 38,000 | 0
Current loans |  | 1,307,417,000 | 846,551,000
Loans | [1] | 1,307,455,000 | 846,551,000
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] |  |  |
Past due loans |  | 220,000 | 191,000
Current loans |  | 52,764,000 | 55,928,000
Loans |  | 52,984,000 | 56,119,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans |  | 181,000 | 134,000
Current loans |  | 567,440,000 | 578,869,000
Loans |  | 567,621,000 | 579,003,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans |  | 25,000 | 0
Current loans |  | 841,120,000 | 835,346,000
Loans |  | 841,145,000 | 835,346,000
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] |  |  |
Past due loans |  | 0 | 0
Current loans |  | 132,047,000 | 124,525,000
Loans |  | 132,047,000 | 124,525,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Retail Portfolio Segment [Member] |  |  |
Past due loans |  | 941,000 | 1,559,000
Current loans |  | 430,863,000 | 413,564,000
Loans |  | 431,804,000 | 415,123,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Past due loans |  | 178,000 | 256,000
Current loans |  | 64,565,000 | 75,118,000
Loans |  | 64,743,000 | 75,374,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans |  | 763,000 | 1,303,000
Current loans |  | 366,298,000 | 338,446,000
Loans |  | 367,061,000 | 339,749,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] |  |  |
Past due loans |  | 287,000 | 1,107,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Past due loans |  | 0 | 191,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans |  | 0 | 191,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Past due loans |  | 287,000 | 916,000
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Past due loans |  | 49,000 | 171,000
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans |  | 238,000 | 745,000
Financial Asset, 60 to 89 Days Past Due [Member] |  |  |
Past due loans |  | 182,000 | 94,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Past due loans |  | 47,000 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans |  | 22,000 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans |  | 25,000 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Past due loans |  | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Past due loans |  | 135,000 | 94,000
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Past due loans |  | 39,000 | 65,000
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans |  | 96,000 | 29,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Past due loans |  | 936,000 | 683,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Past due loans |  | 417,000 | 134,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Past due loans |  | 38,000 | 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] |  |  |
Past due loans |  | 198,000 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans |  | 181,000 | 134,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans |  | 0 | 0
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] |  |  |
Past due loans |  | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Past due loans |  | 519,000 | 549,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Past due loans |  | 90,000 | 20,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans |  | $ 429,000 | $ 529,000
[1] | For June 30, 2020, includes $549 million in loans originated under the Paycheck Protection Program.

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