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Note 4 - Loans and Allowance for Loan Losses (Details) - Impaired Loans - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Originated Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | $ 9,259,000 | $ 8,255,000
Recorded principal balance, with no related allowance | 8,364,000 | 5,552,000
Average recorded principal balance, with no related allowance | 7,370,000 | 7,381,000
Unpaid contractual principal balance, with a related allowance | 14,870,000 | 42,757,000
Recorded principal balance, with a related allowance | 9,833,000 | 42,304,000
Related allowance | 1,474,000 | 10,152,000
Average recorded principal balance, with a related allowance | 22,800,000 | 32,806,000
Upaid contractual principal balance | 24,129,000 | 51,012,000
Recorded principal balance | 18,197,000 | 47,856,000
Average recorded principal balance | 30,170,000 | 40,187,000
Acquired Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 7,368,000 | 4,019,000
Recorded principal balance, with no related allowance | 6,588,000 | 4,010,000
Average recorded principal balance, with no related allowance | 5,741,000 | 1,761,000
Unpaid contractual principal balance, with a related allowance | 632,000 | 1,516,000
Recorded principal balance, with a related allowance | 625,000 | 1,502,000
Related allowance | 112,000 | 605,000
Average recorded principal balance, with a related allowance | 1,156,000 | 501,000
Upaid contractual principal balance | 8,000,000 | 5,535,000
Recorded principal balance | 7,213,000 | 5,512,000
Average recorded principal balance | 6,897,000 | 2,262,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 7,917,000 | 6,904,000
Recorded principal balance, with no related allowance | 7,702,000 | 4,801,000
Average recorded principal balance, with no related allowance | 6,580,000 | 6,279,000
Unpaid contractual principal balance, with a related allowance | 14,105,000 | 40,448,000
Recorded principal balance, with a related allowance | 9,143,000 | 40,220,000
Related allowance | 1,218,000 | 9,374,000
Average recorded principal balance, with a related allowance | 22,035,000 | 30,563,000
Upaid contractual principal balance | 22,022,000 | 47,352,000
Recorded principal balance | 16,845,000 | 45,021,000
Average recorded principal balance | 28,615,000 | 36,842,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 1,509,000 | 1,170,000
Recorded principal balance, with no related allowance | 1,501,000 | 1,164,000
Average recorded principal balance, with no related allowance | 1,683,000 | 652,000
Unpaid contractual principal balance, with a related allowance | 352,000 | 5,299,000
Recorded principal balance, with a related allowance | 305,000 | 5,226,000
Related allowance | 165,000 | 1,578,000
Average recorded principal balance, with a related allowance | 2,314,000 | 2,759,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 0 | 540,000
Recorded principal balance, with no related allowance | 0 | 209,000
Average recorded principal balance, with no related allowance | 81,000 | 227,000
Unpaid contractual principal balance, with a related allowance | 2,017,000 | 2,000,000
Recorded principal balance, with a related allowance | 1,655,000 | 2,000,000
Related allowance | 245,000 | 151,000
Average recorded principal balance, with a related allowance | 1,952,000 | 3,229,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 712,000 | 3,609,000
Recorded principal balance, with no related allowance | 505,000 | 1,901,000
Average recorded principal balance, with no related allowance | 927,000 | 4,365,000
Unpaid contractual principal balance, with a related allowance | 5,867,000 | 15,745,000
Recorded principal balance, with a related allowance | 1,314,000 | 15,674,000
Related allowance | 242,000 | 2,200,000
Average recorded principal balance, with a related allowance | 7,285,000 | 4,630,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 5,696,000 | 1,210,000
Recorded principal balance, with no related allowance | 5,696,000 | 1,210,000
Average recorded principal balance, with no related allowance | 3,703,000 | 971,000
Unpaid contractual principal balance, with a related allowance | 4,841,000 | 16,033,000
Recorded principal balance, with a related allowance | 4,841,000 | 15,949,000
Related allowance | 201,000 | 4,779,000
Average recorded principal balance, with a related allowance | 9,265,000 | 18,245,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 0 | 375,000
Recorded principal balance, with no related allowance | 0 | 317,000
Average recorded principal balance, with no related allowance | 186,000 | 64,000
Unpaid contractual principal balance, with a related allowance | 1,028,000 | 1,371,000
Recorded principal balance, with a related allowance | 1,028,000 | 1,371,000
Related allowance | 365,000 | 666,000
Average recorded principal balance, with a related allowance | 1,219,000 | 1,700,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 5,093,000 | 2,512,000
Recorded principal balance, with no related allowance | 4,730,000 | 2,505,000
Average recorded principal balance, with no related allowance | 4,347,000 | 1,041,000
Unpaid contractual principal balance, with a related allowance | 457,000 | 1,516,000
Recorded principal balance, with a related allowance | 450,000 | 1,502,000
Related allowance | 106,000 | 605,000
Average recorded principal balance, with a related allowance | 971,000 | 501,000
Upaid contractual principal balance | 5,550,000 | 4,028,000
Recorded principal balance | 5,180,000 | 4,007,000
Average recorded principal balance | 5,318,000 | 1,542,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 1,528,000 | 1,586,000
Recorded principal balance, with no related allowance | 1,494,000 | 1,579,000
Average recorded principal balance, with no related allowance | 1,444,000 | 563,000
Unpaid contractual principal balance, with a related allowance | 383,000 | 0
Recorded principal balance, with a related allowance | 376,000 | 0
Related allowance | 102,000 | 0
Average recorded principal balance, with a related allowance | 127,000 | 0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 0 | 0
Recorded principal balance, with no related allowance | 0 | 0
Average recorded principal balance, with no related allowance | 0 | 0
Unpaid contractual principal balance, with a related allowance | 0 | 0
Recorded principal balance, with a related allowance | 0 | 0
Related allowance | 0 | 0
Average recorded principal balance, with a related allowance | 0 | 0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 2,233,000 | 113,000
Recorded principal balance, with no related allowance | 1,952,000 | 113,000
Average recorded principal balance, with no related allowance | 818,000 | 52,000
Unpaid contractual principal balance, with a related allowance | 51,000 | 1,516,000
Recorded principal balance, with a related allowance | 51,000 | 1,502,000
Related allowance | 4,000 | 605,000
Average recorded principal balance, with a related allowance | 823,000 | 501,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 880,000 | 326,000
Recorded principal balance, with no related allowance | 880,000 | 326,000
Average recorded principal balance, with no related allowance | 565,000 | 260,000
Unpaid contractual principal balance, with a related allowance | 0 | 0
Recorded principal balance, with a related allowance | 0 | 0
Related allowance | 0 | 0
Average recorded principal balance, with a related allowance | 0 | 0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 452,000 | 487,000
Recorded principal balance, with no related allowance | 404,000 | 487,000
Average recorded principal balance, with no related allowance | 1,520,000 | 166,000
Unpaid contractual principal balance, with a related allowance | 23,000 | 0
Recorded principal balance, with a related allowance | 23,000 | 0
Related allowance | 0 | 0
Average recorded principal balance, with a related allowance | 21,000 | 0
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 1,342,000 | 1,351,000
Recorded principal balance, with no related allowance | 662,000 | 751,000
Average recorded principal balance, with no related allowance | 790,000 | 1,102,000
Unpaid contractual principal balance, with a related allowance | 765,000 | 2,309,000
Recorded principal balance, with a related allowance | 690,000 | 2,084,000
Related allowance | 256,000 | 778,000
Average recorded principal balance, with a related allowance | 765,000 | 2,243,000
Upaid contractual principal balance | 2,107,000 | 3,660,000
Recorded principal balance | 1,352,000 | 2,835,000
Average recorded principal balance | 1,555,000 | 3,345,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 14,000 | 207,000
Recorded principal balance, with no related allowance | 5,000 | 191,000
Average recorded principal balance, with no related allowance | 153,000 | 517,000
Unpaid contractual principal balance, with a related allowance | 600,000 | 115,000
Recorded principal balance, with a related allowance | 562,000 | 84,000
Related allowance | 209,000 | 84,000
Average recorded principal balance, with a related allowance | 227,000 | 128,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 1,328,000 | 1,144,000
Recorded principal balance, with no related allowance | 657,000 | 560,000
Average recorded principal balance, with no related allowance | 637,000 | 585,000
Unpaid contractual principal balance, with a related allowance | 165,000 | 2,194,000
Recorded principal balance, with a related allowance | 128,000 | 2,000,000
Related allowance | 47,000 | 694,000
Average recorded principal balance, with a related allowance | 538,000 | 2,115,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 2,275,000 | 1,507,000
Recorded principal balance, with no related allowance | 1,858,000 | 1,505,000
Average recorded principal balance, with no related allowance | 1,394,000 | 720,000
Unpaid contractual principal balance, with a related allowance | 175,000 | 0
Recorded principal balance, with a related allowance | 175,000 | 0
Related allowance | 6,000 | 0
Average recorded principal balance, with a related allowance | 185,000 | 0
Upaid contractual principal balance | 2,450,000 | 1,507,000
Recorded principal balance | 2,033,000 | 1,505,000
Average recorded principal balance | 1,579,000 | 720,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 471,000 | 641,000
Recorded principal balance, with no related allowance | 310,000 | 639,000
Average recorded principal balance, with no related allowance | 400,000 | 262,000
Unpaid contractual principal balance, with a related allowance | 0 | 0
Recorded principal balance, with a related allowance | 0 | 0
Related allowance | 0 | 0
Average recorded principal balance, with a related allowance | 0 | 0
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Unpaid contractual principal balance, with no related allowance | 1,804,000 | 866,000
Recorded principal balance, with no related allowance | 1,548,000 | 866,000
Average recorded principal balance, with no related allowance | 994,000 | 458,000
Unpaid contractual principal balance, with a related allowance | 175,000 | 0
Recorded principal balance, with a related allowance | 175,000 | 0
Related allowance | 6,000 | 0
Average recorded principal balance, with a related allowance | $ 185,000 | $ 0

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