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Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Originated Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | $ 5,382,000 |  | $ 4,915,000
With no related allowance recorded, principal balance | 4,616,000 |  | 3,150,000
With no related allowance recorded, average recorded principal balance | 3,883,000 | $ 2,883,000 |
With related allowance recorded, unpaid principal balance | 5,405,000 |  | 5,837,000
With related allowance recorded, principal balance | 4,804,000 |  | 5,637,000
Related allowance | 863,000 |  | 1,867,000
With related allowance recorded, average recorded principal balance | 5,220,000 | 10,913,000 |
Total unpaid principal balance | 10,787,000 |  | 10,752,000
Total principal balance | 9,420,000 |  | 8,787,000
Total average recorded principal balance | 9,103,000 | 13,796,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 3,508,000 |  | 3,096,000
With no related allowance recorded, principal balance | 3,446,000 |  | 2,014,000
With no related allowance recorded, average recorded principal balance | 2,730,000 | 1,987,000 |
With related allowance recorded, unpaid principal balance | 4,485,000 |  | 4,447,000
With related allowance recorded, principal balance | 3,952,000 |  | 4,380,000
Related allowance | 547,000 |  | 1,202,000
With related allowance recorded, average recorded principal balance | 4,165,000 | 10,079,000 |
Total unpaid principal balance | 7,993,000 |  | 7,543,000
Total principal balance | 7,398,000 |  | 6,394,000
Total average recorded principal balance | 6,895,000 | 12,066,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 234,000 |  | 765,000
With no related allowance recorded, principal balance | 234,000 |  | 178,000
With no related allowance recorded, average recorded principal balance | 206,000 | 1,589,000 |
With related allowance recorded, unpaid principal balance | 2,623,000 |  | 3,038,000
With related allowance recorded, principal balance | 2,133,000 |  | 2,989,000
Related allowance | 304,000 |  | 963,000
With related allowance recorded, average recorded principal balance | 2,561,000 | 2,690,000 |
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 | 0 |  | 454,000
With no related allowance recorded, principal balance | 0 |  | 35,000
With no related allowance recorded, average recorded principal balance | 17,000 | 88,000 |
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 | 749,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 2,937,000 |  | 1,528,000
With no related allowance recorded, principal balance | 2,875,000 |  | 1,452,000
With no related allowance recorded, average recorded principal balance | 2,164,000 | 113,000 |
With related allowance recorded, unpaid principal balance | 1,717,000 |  | 1,409,000
With related allowance recorded, principal balance | 1,674,000 |  | 1,391,000
Related allowance | 226,000 |  | 239,000
With related allowance recorded, average recorded principal balance | 1,532,000 | 1,144,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 0 |  | 0
With no related allowance recorded, principal balance | 0 |  | 0
With no related allowance recorded, average recorded principal balance | 0 | 0 |
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 | 4,745,000 |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 337,000 |  | 349,000
With no related allowance recorded, principal balance | 337,000 |  | 349,000
With no related allowance recorded, average recorded principal balance | 343,000 | 197,000 |
With related allowance recorded, unpaid principal balance | 145,000 |  | 0
With related allowance recorded, principal balance | 145,000 |  | 0
Related allowance | 17,000 |  | 0
With related allowance recorded, average recorded principal balance | 72,000 | 751,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 1,874,000 |  | 1,819,000
With no related allowance recorded, principal balance | 1,170,000 |  | 1,136,000
With no related allowance recorded, average recorded principal balance | 1,153,000 | 896,000 |
With related allowance recorded, unpaid principal balance | 920,000 |  | 1,390,000
With related allowance recorded, principal balance | 852,000 |  | 1,257,000
Related allowance | 316,000 |  | 665,000
With related allowance recorded, average recorded principal balance | 1,055,000 | 834,000 |
Total unpaid principal balance | 2,794,000 |  | 3,209,000
Total principal balance | 2,022,000 |  | 2,393,000
Total average recorded principal balance | 2,208,000 | 1,730,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 768,000 |  | 693,000
With no related allowance recorded, principal balance | 751,000 |  | 680,000
With no related allowance recorded, average recorded principal balance | 716,000 | 247,000 |
With related allowance recorded, unpaid principal balance | 508,000 |  | 1,225,000
With related allowance recorded, principal balance | 498,000 |  | 1,147,000
Related allowance | 258,000 |  | 652,000
With related allowance recorded, average recorded principal balance | 823,000 | 697,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 1,106,000 |  | 1,126,000
With no related allowance recorded, principal balance | 419,000 |  | 456,000
With no related allowance recorded, average recorded principal balance | 437,000 | 649,000 |
With related allowance recorded, unpaid principal balance | 412,000 |  | 165,000
With related allowance recorded, principal balance | 354,000 |  | 110,000
Related allowance | 58,000 |  | 13,000
With related allowance recorded, average recorded principal balance | 232,000 | 137,000 |
Acquired Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 5,423,000 |  | 5,938,000
With no related allowance recorded, principal balance | 4,380,000 |  | 4,795,000
With no related allowance recorded, average recorded principal balance | 4,588,000 | 4,952,000 |
With related allowance recorded, unpaid principal balance | 1,597,000 |  | 0
With related allowance recorded, principal balance | 1,597,000 |  | 0
Related allowance | 307,000 |  | 0
With related allowance recorded, average recorded principal balance | 799,000 | 239,000 |
Total unpaid principal balance | 7,020,000 |  | 5,938,000
Total principal balance | 5,977,000 |  | 4,795,000
Total average recorded principal balance | 5,387,000 | 5,191,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 2,147,000 |  | 2,541,000
With no related allowance recorded, principal balance | 1,724,000 |  | 2,135,000
With no related allowance recorded, average recorded principal balance | 1,930,000 | 2,954,000 |
With related allowance recorded, unpaid principal balance | 1,597,000 |  | 0
With related allowance recorded, principal balance | 1,597,000 |  | 0
Related allowance | 307,000 |  | 0
With related allowance recorded, average recorded principal balance | 799,000 | 67,000 |
Total unpaid principal balance | 3,744,000 |  | 2,541,000
Total principal balance | 3,321,000 |  | 2,135,000
Total average recorded principal balance | 2,729,000 | 3,021,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 743,000 |  | 1,039,000
With no related allowance recorded, principal balance | 733,000 |  | 1,021,000
With no related allowance recorded, average recorded principal balance | 877,000 | 892,000 |
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 | 19,000 |
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
With no related allowance recorded, principal balance | 0 |  | 0
With no related allowance recorded, average recorded principal balance | 0 | 0 |
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 | 0 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 1,110,000 |  | 1,027,000
With no related allowance recorded, principal balance | 715,000 |  | 659,000
With no related allowance recorded, average recorded principal balance | 687,000 | 1,151,000 |
With related allowance recorded, unpaid principal balance | 1,597,000 |  | 0
With related allowance recorded, principal balance | 1,597,000 |  | 0
Related allowance | 307,000 |  | 0
With related allowance recorded, average recorded principal balance | 799,000 | 48,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 232,000 |  | 238,000
With no related allowance recorded, principal balance | 232,000 |  | 237,000
With no related allowance recorded, average recorded principal balance | 235,000 | 751,000 |
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 | 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 | 62,000 |  | 237,000
With no related allowance recorded, principal balance | 44,000 |  | 218,000
With no related allowance recorded, average recorded principal balance | 131,000 | 160,000 |
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 | 0 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 3,276,000 |  | 3,397,000
With no related allowance recorded, principal balance | 2,656,000 |  | 2,660,000
With no related allowance recorded, average recorded principal balance | 2,658,000 | 1,998,000 |
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 | 172,000 |
Total unpaid principal balance | 3,276,000 |  | 3,397,000
Total principal balance | 2,656,000 |  | 2,660,000
Total average recorded principal balance | 2,658,000 | 2,170,000 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 690,000 |  | 694,000
With no related allowance recorded, principal balance | 649,000 |  | 507,000
With no related allowance recorded, average recorded principal balance | 578,000 | 336,000 |
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 | 0 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
With no related allowance recorded, unpaid principal balance | 2,586,000 |  | 2,703,000
With no related allowance recorded, principal balance | 2,007,000 |  | 2,153,000
With no related allowance recorded, average recorded principal balance | 2,080,000 | 1,662,000 |
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 | $ 172,000 |

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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524 + Details
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