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Note 4 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Originated Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | $ 3,499,000 | $ 9,259,000
With no related allowance recorded, principal balance | 2,467,000 | 8,364,000
With no related allowance recorded, average recorded principal balance | 6,583,000 | 7,370,000
With related allowance recorded, unpaid principal balance | 11,008,000 | 14,870,000
With related allowance recorded, principal balance | 10,916,000 | 9,833,000
Related allowance | 1,572,000 | 1,474,000
With related allowance recorded, average recorded principal balance | 8,869,000 | 22,800,000
Total unpaid principal balance | 14,507,000 | 24,129,000
Total principal balance | 13,383,000 | 18,197,000
Total average recorded principal balance | 15,452,000 | 30,170,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |
With no related allowance recorded, unpaid principal balance | 2,115,000 | 7,917,000
With no related allowance recorded, principal balance | 1,723,000 | 7,702,000
With no related allowance recorded, average recorded principal balance | 5,671,000 | 6,580,000
With related allowance recorded, unpaid principal balance | 10,370,000 | 14,105,000
With related allowance recorded, principal balance | 10,347,000 | 9,143,000
Related allowance | 1,303,000 | 1,218,000
With related allowance recorded, average recorded principal balance | 8,276,000 | 22,035,000
Total unpaid principal balance | 12,485,000 | 22,022,000
Total principal balance | 12,070,000 | 16,845,000
Total average recorded principal balance | 13,947,000 | 28,615,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
With no related allowance recorded, unpaid principal balance | 1,498,000 | 1,509,000
With no related allowance recorded, principal balance | 1,498,000 | 1,501,000
With no related allowance recorded, average recorded principal balance | 1,574,000 | 1,683,000
With related allowance recorded, unpaid principal balance | 2,405,000 | 352,000
With related allowance recorded, principal balance | 2,382,000 | 305,000
Related allowance | 673,000 | 165,000
With related allowance recorded, average recorded principal balance | 717,000 | 2,314,000
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 | 487,000 | 0
With no related allowance recorded, principal balance | 95,000 | 0
With no related allowance recorded, average recorded principal balance | 32,000 | 81,000
With related allowance recorded, unpaid principal balance | 999,000 | 2,017,000
With related allowance recorded, principal balance | 999,000 | 1,655,000
Related allowance | 28,000 | 245,000
With related allowance recorded, average recorded principal balance | 1,011,000 | 1,952,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 0 | 712,000
With no related allowance recorded, principal balance | 0 | 505,000
With no related allowance recorded, average recorded principal balance | 270,000 | 927,000
With related allowance recorded, unpaid principal balance | 906,000 | 5,867,000
With related allowance recorded, principal balance | 906,000 | 1,314,000
Related allowance | 97,000 | 242,000
With related allowance recorded, average recorded principal balance | 2,095,000 | 7,285,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 0 | 5,696,000
With no related allowance recorded, principal balance | 0 | 5,696,000
With no related allowance recorded, average recorded principal balance | 3,752,000 | 3,703,000
With related allowance recorded, unpaid principal balance | 5,020,000 | 4,841,000
With related allowance recorded, principal balance | 5,020,000 | 4,841,000
Related allowance | 247,000 | 201,000
With related allowance recorded, average recorded principal balance | 3,641,000 | 9,265,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 130,000 | 0
With no related allowance recorded, principal balance | 130,000 | 0
With no related allowance recorded, average recorded principal balance | 43,000 | 186,000
With related allowance recorded, unpaid principal balance | 1,040,000 | 1,028,000
With related allowance recorded, principal balance | 1,040,000 | 1,028,000
Related allowance | 258,000 | 365,000
With related allowance recorded, average recorded principal balance | 812,000 | 1,219,000
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |
With no related allowance recorded, unpaid principal balance | 1,384,000 | 1,342,000
With no related allowance recorded, principal balance | 744,000 | 662,000
With no related allowance recorded, average recorded principal balance | 912,000 | 790,000
With related allowance recorded, unpaid principal balance | 638,000 | 765,000
With related allowance recorded, principal balance | 569,000 | 690,000
Related allowance | 269,000 | 256,000
With related allowance recorded, average recorded principal balance | 593,000 | 765,000
Total unpaid principal balance | 2,022,000 | 2,107,000
Total principal balance | 1,313,000 | 1,352,000
Total average recorded principal balance | 1,505,000 | 1,555,000
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
With no related allowance recorded, unpaid principal balance | 114,000 | 14,000
With no related allowance recorded, principal balance | 114,000 | 5,000
With no related allowance recorded, average recorded principal balance | 99,000 | 153,000
With related allowance recorded, unpaid principal balance | 434,000 | 600,000
With related allowance recorded, principal balance | 412,000 | 562,000
Related allowance | 203,000 | 209,000
With related allowance recorded, average recorded principal balance | 449,000 | 227,000
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
With no related allowance recorded, unpaid principal balance | 1,270,000 | 1,328,000
With no related allowance recorded, principal balance | 630,000 | 657,000
With no related allowance recorded, average recorded principal balance | 813,000 | 637,000
With related allowance recorded, unpaid principal balance | 204,000 | 165,000
With related allowance recorded, principal balance | 157,000 | 128,000
Related allowance | 66,000 | 47,000
With related allowance recorded, average recorded principal balance | 144,000 | 538,000
Acquired Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 5,826,000 | 7,368,000
With no related allowance recorded, principal balance | 4,894,000 | 6,588,000
With no related allowance recorded, average recorded principal balance | 5,405,000 | 5,741,000
With related allowance recorded, unpaid principal balance | 239,000 | 632,000
With related allowance recorded, principal balance | 239,000 | 625,000
Related allowance | 9,000 | 112,000
With related allowance recorded, average recorded principal balance | 370,000 | 1,156,000
Total unpaid principal balance | 6,065,000 | 8,000,000
Total principal balance | 5,133,000 | 7,213,000
Total average recorded principal balance | 5,775,000 | 6,897,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |
With no related allowance recorded, unpaid principal balance | 3,214,000 | 5,093,000
With no related allowance recorded, principal balance | 2,914,000 | 4,730,000
With no related allowance recorded, average recorded principal balance | 3,454,000 | 4,347,000
With related allowance recorded, unpaid principal balance | 67,000 | 457,000
With related allowance recorded, principal balance | 67,000 | 450,000
Related allowance | 5,000 | 106,000
With related allowance recorded, average recorded principal balance | 250,000 | 971,000
Total unpaid principal balance | 3,281,000 | 5,550,000
Total principal balance | 2,981,000 | 5,180,000
Total average recorded principal balance | 3,704,000 | 5,318,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
With no related allowance recorded, unpaid principal balance | 853,000 | 1,528,000
With no related allowance recorded, principal balance | 826,000 | 1,494,000
With no related allowance recorded, average recorded principal balance | 1,074,000 | 1,444,000
With related allowance recorded, unpaid principal balance | 19,000 | 383,000
With related allowance recorded, principal balance | 19,000 | 376,000
Related allowance | 2,000 | 102,000
With related allowance recorded, average recorded principal balance | 207,000 | 127,000
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 | 1,281,000 | 2,233,000
With no related allowance recorded, principal balance | 1,210,000 | 1,952,000
With no related allowance recorded, average recorded principal balance | 1,145,000 | 818,000
With related allowance recorded, unpaid principal balance | 48,000 | 51,000
With related allowance recorded, principal balance | 48,000 | 51,000
Related allowance | 3,000 | 4,000
With related allowance recorded, average recorded principal balance | 38,000 | 823,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 928,000 | 880,000
With no related allowance recorded, principal balance | 789,000 | 880,000
With no related allowance recorded, average recorded principal balance | 932,000 | 565,000
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 Residentia lRental Loan [Member] |  |
With no related allowance recorded, unpaid principal balance | 152,000 | 452,000
With no related allowance recorded, principal balance | 89,000 | 404,000
With no related allowance recorded, average recorded principal balance | 303,000 | 1,520,000
With related allowance recorded, unpaid principal balance | 0 | 23,000
With related allowance recorded, principal balance | 0 | 23,000
Related allowance | 0 | 0
With related allowance recorded, average recorded principal balance | 5,000 | 21,000
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |
With no related allowance recorded, unpaid principal balance | 2,612,000 | 2,275,000
With no related allowance recorded, principal balance | 1,980,000 | 1,858,000
With no related allowance recorded, average recorded principal balance | 1,951,000 | 1,394,000
With related allowance recorded, unpaid principal balance | 172,000 | 175,000
With related allowance recorded, principal balance | 172,000 | 175,000
Related allowance | 4,000 | 6,000
With related allowance recorded, average recorded principal balance | 120,000 | 185,000
Total unpaid principal balance | 2,784,000 | 2,450,000
Total principal balance | 2,152,000 | 2,033,000
Total average recorded principal balance | 2,071,000 | 1,579,000
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
With no related allowance recorded, unpaid principal balance | 531,000 | 471,000
With no related allowance recorded, principal balance | 351,000 | 310,000
With no related allowance recorded, average recorded principal balance | 389,000 | 400,000
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 | 2,081,000 | 1,804,000
With no related allowance recorded, principal balance | 1,629,000 | 1,548,000
With no related allowance recorded, average recorded principal balance | 1,562,000 | 994,000
With related allowance recorded, unpaid principal balance | 172,000 | 175,000
With related allowance recorded, principal balance | 172,000 | 175,000
Related allowance | 4,000 | 6,000
With related allowance recorded, average recorded principal balance | $ 120,000 | $ 185,000

X
- 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 + Details
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