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Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Originated Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | $ 4,139,000 |  | $ 4,139,000 |  | $ 4,915,000
With no related allowance recorded, principal balance | 3,039,000 |  | 3,039,000 |  | 3,150,000
With no related allowance recorded, average recorded principal balance | 2,459,000 | $ 1,992,000 | 3,171,000 | $ 2,439,000 |
With related allowance recorded, unpaid principal balance | 9,004,000 |  | 9,004,000 |  | 5,837,000
With related allowance recorded, principal balance | 8,906,000 |  | 8,906,000 |  | 5,637,000
Related allowance | 998,000 |  | 998,000 |  | 1,867,000
With related allowance recorded, average recorded principal balance | 6,841,000 | 8,654,000 | 6,031,000 | 9,783,000 |
Total unpaid principal balance | 13,143,000 |  | 13,143,000 |  | 10,752,000
Total principal balance | 11,945,000 |  | 11,945,000 |  | 8,787,000
Total average recorded principal balance | 9,300,000 | 10,646,000 | 9,202,000 | 12,222,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 2,195,000 |  | 2,195,000 |  | 3,096,000
With no related allowance recorded, principal balance | 1,804,000 |  | 1,804,000 |  | 2,014,000
With no related allowance recorded, average recorded principal balance | 1,338,000 | 649,000 | 2,034,000 | 1,319,000 |
With related allowance recorded, unpaid principal balance | 8,147,000 |  | 8,147,000 |  | 4,447,000
With related allowance recorded, principal balance | 8,125,000 |  | 8,125,000 |  | 4,380,000
Related allowance | 750,000 |  | 750,000 |  | 1,202,000
With related allowance recorded, average recorded principal balance | 6,032,000 | 7,506,000 | 5,099,000 | 8,792,000 |
Total unpaid principal balance | 10,342,000 |  | 10,342,000 |  | 7,543,000
Total principal balance | 9,929,000 |  | 9,929,000 |  | 6,394,000
Total average recorded principal balance | 7,370,000 | 8,155,000 | 7,133,000 | 10,111,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 1,294,000 |  | 1,294,000 |  | 765,000
With no related allowance recorded, principal balance | 951,000 |  | 951,000 |  | 178,000
With no related allowance recorded, average recorded principal balance | 732,000 | 56,000 | 469,000 | 823,000 |
With related allowance recorded, unpaid principal balance | 5,102,000 |  | 5,102,000 |  | 3,038,000
With related allowance recorded, principal balance | 5,099,000 |  | 5,099,000 |  | 2,989,000
Related allowance | 348,000 |  | 348,000 |  | 963,000
With related allowance recorded, average recorded principal balance | 3,572,000 | 4,100,000 | 3,067,000 | 3,395,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 96,000 |  | 96,000 |  | 454,000
With no related allowance recorded, principal balance | 96,000 |  | 96,000 |  | 35,000
With no related allowance recorded, average recorded principal balance | 98,000 | 58,000 | 58,000 | 73,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 374,000 | 0 | 561,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 783,000 |  | 783,000 |  | 1,528,000
With no related allowance recorded, principal balance | 735,000 |  | 735,000 |  | 1,452,000
With no related allowance recorded, average recorded principal balance | 383,000 | 266,000 | 1,273,000 | 189,000 |
With related allowance recorded, unpaid principal balance | 2,903,000 |  | 2,903,000 |  | 1,409,000
With related allowance recorded, principal balance | 2,887,000 |  | 2,887,000 |  | 1,391,000
Related allowance | 386,000 |  | 386,000 |  | 239,000
With related allowance recorded, average recorded principal balance | 2,320,000 | 2,319,000 | 1,926,000 | 1,731,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With no related allowance recorded, principal balance | 0 |  | 0 |  | 0
With no related allowance recorded, average recorded principal balance | 0 | 89,000 | 0 | 45,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 392,000 | 0 | 2,569,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 22,000 |  | 22,000 |  | 349,000
With no related allowance recorded, principal balance | 22,000 |  | 22,000 |  | 349,000
With no related allowance recorded, average recorded principal balance | 125,000 | 180,000 | 234,000 | 189,000 |
With related allowance recorded, unpaid principal balance | 142,000 |  | 142,000 |  | 0
With related allowance recorded, principal balance | 139,000 |  | 139,000 |  | 0
Related allowance | 16,000 |  | 16,000 |  | 0
With related allowance recorded, average recorded principal balance | 140,000 | 321,000 | 106,000 | 536,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 1,944,000 |  | 1,944,000 |  | 1,819,000
With no related allowance recorded, principal balance | 1,235,000 |  | 1,235,000 |  | 1,136,000
With no related allowance recorded, average recorded principal balance | 1,121,000 | 1,343,000 | 1,137,000 | 1,120,000 |
With related allowance recorded, unpaid principal balance | 857,000 |  | 857,000 |  | 1,390,000
With related allowance recorded, principal balance | 781,000 |  | 781,000 |  | 1,257,000
Related allowance | 248,000 |  | 248,000 |  | 665,000
With related allowance recorded, average recorded principal balance | 809,000 | 1,148,000 | 932,000 | 991,000 |
Total unpaid principal balance | 2,801,000 |  | 2,801,000 |  | 3,209,000
Total principal balance | 2,016,000 |  | 2,016,000 |  | 2,393,000
Total average recorded principal balance | 1,930,000 | 2,491,000 | 2,069,000 | 2,111,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 853,000 |  | 853,000 |  | 693,000
With no related allowance recorded, principal balance | 821,000 |  | 821,000 |  | 680,000
With no related allowance recorded, average recorded principal balance | 719,000 | 729,000 | 717,000 | 488,000 |
With related allowance recorded, unpaid principal balance | 447,000 |  | 447,000 |  | 1,225,000
With related allowance recorded, principal balance | 436,000 |  | 436,000 |  | 1,147,000
Related allowance | 199,000 |  | 199,000 |  | 652,000
With related allowance recorded, average recorded principal balance | 463,000 | 1,035,000 | 643,000 | 866,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 1,091,000 |  | 1,091,000 |  | 1,126,000
With no related allowance recorded, principal balance | 414,000 |  | 414,000 |  | 456,000
With no related allowance recorded, average recorded principal balance | 402,000 | 614,000 | 420,000 | 632,000 |
With related allowance recorded, unpaid principal balance | 410,000 |  | 410,000 |  | 165,000
With related allowance recorded, principal balance | 345,000 |  | 345,000 |  | 110,000
Related allowance | 49,000 |  | 49,000 |  | 13,000
With related allowance recorded, average recorded principal balance | 346,000 | 113,000 | 289,000 | 125,000 |
Acquired Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 4,919,000 |  | 4,919,000 |  | 5,938,000
With no related allowance recorded, principal balance | 4,318,000 |  | 4,318,000 |  | 4,795,000
With no related allowance recorded, average recorded principal balance | 4,346,000 | 6,410,000 | 4,469,000 | 5,680,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 34,000 | 223,000 | 412,000 | 230,000 |
Total unpaid principal balance | 4,919,000 |  | 4,919,000 |  | 5,938,000
Total principal balance | 4,318,000 |  | 4,318,000 |  | 4,795,000
Total average recorded principal balance | 4,380,000 | 6,633,000 | 4,881,000 | 5,910,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 1,408,000 |  | 1,408,000 |  | 2,541,000
With no related allowance recorded, principal balance | 1,380,000 |  | 1,380,000 |  | 2,135,000
With no related allowance recorded, average recorded principal balance | 1,495,000 | 3,983,000 | 1,714,000 | 3,468,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 53,000 | 400,000 | 59,000 |
Total unpaid principal balance | 1,408,000 |  | 1,408,000 |  | 2,541,000
Total principal balance | 1,380,000 |  | 1,380,000 |  | 2,135,000
Total average recorded principal balance | 1,495,000 | 4,036,000 | 2,114,000 | 3,527,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 598,000 |  | 598,000 |  | 1,039,000
With no related allowance recorded, principal balance | 589,000 |  | 589,000 |  | 1,021,000
With no related allowance recorded, average recorded principal balance | 648,000 | 1,196,000 | 763,000 | 1,044,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 6,000 | 0 | 12,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With no related allowance recorded, principal balance | 0 |  | 0 |  | 0
With no related allowance recorded, average recorded principal balance | 0 | 31,000 | 0 | 15,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 0 | 0 | 0 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 538,000 |  | 538,000 |  | 1,027,000
With no related allowance recorded, principal balance | 538,000 |  | 538,000 |  | 659,000
With no related allowance recorded, average recorded principal balance | 588,000 | 1,031,000 | 638,000 | 1,091,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 47,000 | 400,000 | 47,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 217,000 |  | 217,000 |  | 238,000
With no related allowance recorded, principal balance | 217,000 |  | 217,000 |  | 237,000
With no related allowance recorded, average recorded principal balance | 221,000 | 975,000 | 228,000 | 863,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 0 | 0 | 0 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 55,000 |  | 55,000 |  | 237,000
With no related allowance recorded, principal balance | 36,000 |  | 36,000 |  | 218,000
With no related allowance recorded, average recorded principal balance | 38,000 | 750,000 | 85,000 | 455,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 0 | 0 | 0 | 0 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 3,511,000 |  | 3,511,000 |  | 3,397,000
With no related allowance recorded, principal balance | 2,938,000 |  | 2,938,000 |  | 2,660,000
With no related allowance recorded, average recorded principal balance | 2,851,000 | 2,427,000 | 2,755,000 | 2,212,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 34,000 | 170,000 | 12,000 | 171,000 |
Total unpaid principal balance | 3,511,000 |  | 3,511,000 |  | 3,397,000
Total principal balance | 2,938,000 |  | 2,938,000 |  | 2,660,000
Total average recorded principal balance | 2,885,000 | 2,597,000 | 2,767,000 | 2,383,000 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 830,000 |  | 830,000 |  | 694,000
With no related allowance recorded, principal balance | 785,000 |  | 785,000 |  | 507,000
With no related allowance recorded, average recorded principal balance | 778,000 | 453,000 | 678,000 | 394,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | 0
With related allowance recorded, average recorded principal balance | 34,000 | 0 | 12,000 | 0 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |  |  |
With no related allowance recorded, unpaid principal balance | 2,681,000 |  | 2,681,000 |  | 2,703,000
With no related allowance recorded, principal balance | 2,153,000 |  | 2,153,000 |  | 2,153,000
With no related allowance recorded, average recorded principal balance | 2,073,000 | 1,974,000 | 2,077,000 | 1,818,000 |
With related allowance recorded, unpaid principal balance | 0 |  | 0 |  | 0
With related allowance recorded, principal balance | 0 |  | 0 |  | 0
Related allowance | 0 |  | 0 |  | $ 0
With related allowance recorded, average recorded principal balance | $ 0 | $ 170,000 | $ 0 | $ 171,000 |

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