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Note 4 - Loans and Allowance for Loan Losses (Details) - Age Analysis of Past Due Loans - USD ($) | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | --- | ---
Commercial: |  |  |
Loans | $ 2,277,727,000 | $ 2,089,277,000 |
Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,293,000 | 643,000 |
Loans, current | 1,615,294,000 | 1,245,473,000 |
Loans | 1,616,587,000 | 1,246,116,000 | $ 1,053,243,000
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Originated Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 725,000 | 38,000 |
Originated Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 203,000 | 3,000 |
Originated Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 365,000 | 602,000 |
Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 5,772,000 | 6,743,000 |
Loans, current | 655,368,000 | 836,418,000 |
Loans | 661,140,000 | 843,161,000 |
Loans, recorded balance > 89 days and accruing | 5,000 | 26,000 |
Acquired Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,981,000 | 1,717,000 |
Acquired Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,585,000 | 1,920,000 |
Acquired Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 2,206,000 | 3,106,000 |
Commercial Portfolio Segment [Member] |  |  |
Commercial: |  |  |
Loans | 1,946,696,000 | 1,715,303,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Commercial: |  |  |
Loans | 696,303,000 | 550,607,000 |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Commercial: |  |  |
Loans | 45,120,000 | 51,974,000 |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans | 445,919,000 | 430,388,000 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans | 644,351,000 | 559,574,000 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Commercial: |  |  |
Loans | 115,003,000 | 122,760,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 441,000 | 236,000 |
Loans, current | 1,493,075,000 | 1,152,953,000 |
Loans | 1,493,516,000 | 1,153,189,000 | 986,696,000
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 432,000 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 9,000 | 236,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Loans, current | 577,872,000 | 384,570,000 |
Loans | 577,872,000 | 384,570,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Loans, current | 30,138,000 | 29,826,000 |
Loans | 30,138,000 | 29,826,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 441,000 | 120,000 |
Loans, current | 330,357,000 | 291,638,000 |
Loans | 330,798,000 | 291,758,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 432,000 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 9,000 | 120,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 116,000 |
Loans, current | 520,754,000 | 410,861,000 |
Loans | 520,754,000 | 410,977,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 116,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Loans, current | 33,954,000 | 36,058,000 |
Loans | 33,954,000 | 36,058,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 3,575,000 | 3,479,000 |
Loans, current | 449,605,000 | 558,635,000 |
Loans | 453,180,000 | 562,114,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 626,000 | 185,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,187,000 | 1,093,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,762,000 | 2,201,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Commercial: |  |  |
Loans, past due | 546,000 | 137,000 |
Loans, current | 117,885,000 | 165,900,000 |
Loans | 118,431,000 | 166,037,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 29,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 5,000 | 32,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 541,000 | 76,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 27,000 | 38,000 |
Loans, current | 14,955,000 | 22,110,000 |
Loans | 14,982,000 | 22,148,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 27,000 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 38,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,890,000 | 2,101,000 |
Loans, current | 113,231,000 | 136,529,000 |
Loans | 115,121,000 | 138,630,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 323,000 | 51,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 425,000 | 425,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,142,000 | 1,625,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 835,000 | 1,061,000 |
Loans, current | 122,762,000 | 147,536,000 |
Loans | 123,597,000 | 148,597,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 53,000 | 68,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 703,000 | 598,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 79,000 | 395,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 277,000 | 142,000 |
Loans, current | 80,772,000 | 86,560,000 |
Loans | 81,049,000 | 86,702,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 223,000 | 37,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 54,000 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 105,000 |
Retail Portfolio Segment [Member] |  |  |
Commercial: |  |  |
Loans | 331,031,000 | 373,974,000 |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Commercial: |  |  |
Loans | 140,646,000 | 159,278,000 |
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member] |  |  |
Commercial: |  |  |
Loans | 190,385,000 | 214,696,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 852,000 | 407,000 |
Loans, current | 122,219,000 | 92,520,000 |
Loans | 123,071,000 | 92,927,000 | $ 66,547,000
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 293,000 | 38,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 203,000 | 3,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 356,000 | 366,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Commercial: |  |  |
Loans, past due | 294,000 | 41,000 |
Loans, current | 67,522,000 | 50,018,000 |
Loans | 67,816,000 | 50,059,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 186,000 | 38,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 108,000 | 3,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 0 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Commercial: |  |  |
Loans, past due | 558,000 | 366,000 |
Loans, current | 54,697,000 | 42,502,000 |
Loans | 55,255,000 | 42,868,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 107,000 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 95,000 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 356,000 | 366,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans, past due | 2,197,000 | 3,264,000 |
Loans, current | 205,763,000 | 277,783,000 |
Loans | 207,960,000 | 281,047,000 |
Loans, recorded balance > 89 days and accruing | 5,000 | 26,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,355,000 | 1,532,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 398,000 | 827,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 444,000 | 905,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Commercial: |  |  |
Loans, past due | 467,000 | 1,019,000 |
Loans, current | 72,363,000 | 108,200,000 |
Loans | 72,830,000 | 109,219,000 |
Loans, recorded balance > 89 days and accruing | 5,000 | 26,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 395,000 | 445,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 44,000 | 419,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 28,000 | 155,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Commercial: |  |  |
Loans, past due | 1,730,000 | 2,245,000 |
Loans, current | 133,400,000 | 169,583,000 |
Loans | 135,130,000 | 171,828,000 |
Loans, recorded balance > 89 days and accruing | 0 | 0 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 960,000 | 1,087,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | 354,000 | 408,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |
Commercial: |  |  |
Loans, past due | $ 416,000 | $ 750,000 |

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