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Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
With no related allowance recorded, unpaid principal balance | $ 26,892,000 | $ 13,687,000
With no related allowance recorded, principal balance | 24,738,000 | 12,245,000
With no related allowance recorded, average recorded principal balance | 17,315,000 | 16,675,000
With related allowance recorded, unpaid principal balance | 2,266,000 | 2,398,000
With related allowance recorded, principal balance | 2,220,000 | 2,377,000
Related allowance | 551,000 | 1,623,000
With related allowance recorded, average recorded principal balance | 2,742,000 | 8,833,000
Total unpaid principal balance | 29,158,000 | 16,085,000
Total principal balance | 26,958,000 | 14,622,000
Total average recorded principal balance | 20,057,000 | 25,508,000
Commercial Portfolio Segment [Member] |  |
With no related allowance recorded, unpaid principal balance | 21,365,000 | 9,136,000
With no related allowance recorded, principal balance | 21,176,000 | 9,068,000
With no related allowance recorded, average recorded principal balance | 13,652,000 | 13,394,000
With related allowance recorded, unpaid principal balance | 1,268,000 | 1,538,000
With related allowance recorded, principal balance | 1,239,000 | 1,536,000
Related allowance | 138,000 | 1,184,000
With related allowance recorded, average recorded principal balance | 1,726,000 | 7,515,000
Total unpaid principal balance | 22,633,000 | 10,674,000
Total principal balance | 22,415,000 | 10,604,000
Total average recorded principal balance | 15,378,000 | 20,909,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
With no related allowance recorded, unpaid principal balance | 6,242,000 | 8,129,000
With no related allowance recorded, principal balance | 6,242,000 | 8,129,000
With no related allowance recorded, average recorded principal balance | 7,874,000 | 11,610,000
With related allowance recorded, unpaid principal balance | 343,000 | 460,000
With related allowance recorded, principal balance | 343,000 | 458,000
Related allowance | 53,000 | 202,000
With related allowance recorded, average recorded principal balance | 971,000 | 5,709,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 0 | 85,000
With no related allowance recorded, principal balance | 0 | 85,000
With no related allowance recorded, average recorded principal balance | 187,000 | 89,000
With related allowance recorded, unpaid principal balance | 0 | 0
With related allowance recorded, principal balance | 0 | 0
Related allowance | 0 | 0
With related allowance recorded, average recorded principal balance | 77,000 | 0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 14,782,000 | 715,000
With no related allowance recorded, principal balance | 14,593,000 | 667,000
With no related allowance recorded, average recorded principal balance | 5,361,000 | 1,520,000
With related allowance recorded, unpaid principal balance | 763,000 | 1,078,000
With related allowance recorded, principal balance | 734,000 | 1,078,000
Related allowance | 77,000 | 982,000
With related allowance recorded, average recorded principal balance | 578,000 | 1,672,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 341,000 | 178,000
With no related allowance recorded, principal balance | 341,000 | 178,000
With no related allowance recorded, average recorded principal balance | 227,000 | 131,000
With related allowance recorded, unpaid principal balance | 162,000 | 0
With related allowance recorded, principal balance | 162,000 | 0
Related allowance | 8,000 | 0
With related allowance recorded, average recorded principal balance | 100,000 | 80,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 0 | 29,000
With no related allowance recorded, principal balance | 0 | 9,000
With no related allowance recorded, average recorded principal balance | 3,000 | 44,000
With related allowance recorded, unpaid principal balance | 0 | 0
With related allowance recorded, principal balance | 0 | 0
Related allowance | 0 | 0
With related allowance recorded, average recorded principal balance | 0 | 54,000
Retail Portfolio Segment [Member] |  |
With no related allowance recorded, unpaid principal balance | 5,527,000 | 4,551,000
With no related allowance recorded, principal balance | 3,562,000 | 3,177,000
With no related allowance recorded, average recorded principal balance | 3,663,000 | 3,281,000
With related allowance recorded, unpaid principal balance | 998,000 | 860,000
With related allowance recorded, principal balance | 981,000 | 841,000
Related allowance | 413,000 | 439,000
With related allowance recorded, average recorded principal balance | 1,016,000 | 1,318,000
Total unpaid principal balance | 6,525,000 | 5,411,000
Total principal balance | 4,543,000 | 4,018,000
Total average recorded principal balance | 4,679,000 | 4,599,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
With no related allowance recorded, unpaid principal balance | 1,072,000 | 1,279,000
With no related allowance recorded, principal balance | 987,000 | 1,209,000
With no related allowance recorded, average recorded principal balance | 1,216,000 | 1,203,000
With related allowance recorded, unpaid principal balance | 300,000 | 502,000
With related allowance recorded, principal balance | 283,000 | 485,000
Related allowance | 241,000 | 356,000
With related allowance recorded, average recorded principal balance | 421,000 | 658,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
With no related allowance recorded, unpaid principal balance | 4,455,000 | 3,272,000
With no related allowance recorded, principal balance | 2,575,000 | 1,968,000
With no related allowance recorded, average recorded principal balance | 2,447,000 | 2,078,000
With related allowance recorded, unpaid principal balance | 698,000 | 358,000
With related allowance recorded, principal balance | 698,000 | 356,000
Related allowance | 172,000 | 83,000
With related allowance recorded, average recorded principal balance | $ 595,000 | $ 660,000

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