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Note 4 - Loans and Allowance for Loan Losses - Age Analysis of Past Due Loans (Details) - USD ($) | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | ---
Loans | $ 2,378,620,000 | $ 2,277,727,000 |
Originated Loan [Member] |  |  |
Past due loans | 1,388,000 | 1,293,000 |
Current loans | 1,883,160,000 | 1,615,294,000 |
Loans | 1,884,548,000 | 1,616,587,000 | $ 1,246,116,000
Loans past due 90 days or more still accruing interest | 0 | 0 |
Acquired Loan [Member] |  |  |
Past due loans | 2,999,000 | 5,772,000 |
Current loans | 491,073,000 | 655,368,000 |
Loans | 494,072,000 | 661,140,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] |  |  |
Loans | 2,065,347,000 | 1,946,696,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | 713,903,000 | 696,303,000 |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | 34,828,000 | 45,120,000 |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | 450,464,000 | 445,919,000 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | 748,269,000 | 644,351,000 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Loans | 117,883,000 | 115,003,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 27,000 | 441,000 |
Current loans | 1,728,871,000 | 1,493,075,000 |
Loans | 1,728,898,000 | 1,493,516,000 | 1,153,189,000
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 27,000 | 0 |
Current loans | 636,744,000 | 577,872,000 |
Loans | 636,771,000 | 577,872,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 0 |
Current loans | 26,519,000 | 30,138,000 |
Loans | 26,519,000 | 30,138,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 441,000 |
Current loans | 363,509,000 | 330,357,000 |
Loans | 363,509,000 | 330,798,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 0 |
Current loans | 652,054,000 | 520,754,000 |
Loans | 652,054,000 | 520,754,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 0 | 0 |
Current loans | 50,045,000 | 33,954,000 |
Loans | 50,045,000 | 33,954,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 509,000 | 3,575,000 |
Current loans | 335,940,000 | 449,605,000 |
Loans | 336,449,000 | 453,180,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 27,000 | 546,000 |
Current loans | 77,105,000 | 117,885,000 |
Loans | 77,132,000 | 118,431,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 27,000 |
Current loans | 8,309,000 | 14,955,000 |
Loans | 8,309,000 | 14,982,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 112,000 | 1,890,000 |
Current loans | 86,843,000 | 113,231,000 |
Loans | 86,955,000 | 115,121,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 353,000 | 835,000 |
Current loans | 95,862,000 | 122,762,000 |
Loans | 96,215,000 | 123,597,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 17,000 | 277,000 |
Current loans | 67,821,000 | 80,772,000 |
Loans | 67,838,000 | 81,049,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Retail Portfolio Segment [Member] |  |  |
Loans | 313,273,000 | 331,031,000 |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | 118,047,000 | 140,646,000 |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | 195,226,000 | 190,385,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 1,361,000 | 852,000 |
Current loans | 154,289,000 | 122,219,000 |
Loans | 155,650,000 | 123,071,000 | $ 92,927,000
Loans past due 90 days or more still accruing interest | 0 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 144,000 | 294,000 |
Current loans | 69,687,000 | 67,522,000 |
Loans | 69,831,000 | 67,816,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Retail Portfolio Segment [Member] | Originated Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 1,217,000 | 558,000 |
Current loans | 84,602,000 | 54,697,000 |
Loans | 85,819,000 | 55,255,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 2,490,000 | 2,197,000 |
Current loans | 155,133,000 | 205,763,000 |
Loans | 157,623,000 | 207,960,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 329,000 | 467,000 |
Current loans | 47,887,000 | 72,363,000 |
Loans | 48,216,000 | 72,830,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 2,161,000 | 1,730,000 |
Current loans | 107,246,000 | 133,400,000 |
Loans | 109,407,000 | 135,130,000 |
Loans past due 90 days or more still accruing interest | 0 | 0 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Past due loans | 804,000 | 725,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Past due loans | 1,575,000 | 1,981,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 0 | 432,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 432,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 62,000 | 626,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 27,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 62,000 | 323,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 53,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 0 | 223,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 804,000 | 293,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 46,000 | 186,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 758,000 | 107,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 1,513,000 | 1,355,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 258,000 | 395,000 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 1,255,000 | 960,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Past due loans | 247,000 | 203,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Past due loans | 504,000 | 1,585,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 27,000 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 27,000 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 11,000 | 1,187,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 11,000 | 5,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 425,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 703,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 0 | 54,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 220,000 | 203,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 98,000 | 108,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 122,000 | 95,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 493,000 | 398,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 26,000 | 44,000 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 467,000 | 354,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Past due loans | 337,000 | 365,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Past due loans | 920,000 | 2,206,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 0 | 9,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 9,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 436,000 | 1,762,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Past due loans | 16,000 | 541,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Past due loans | 50,000 | 1,142,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Past due loans | 353,000 | 79,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Past due loans | 17,000 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Past due loans | 337,000 | 356,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 0 | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Originated Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | 337,000 | 356,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Past due loans | 484,000 | 444,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Past due loans | 45,000 | 28,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Acquired Loan [Member] | One to Four Family Mortgages [Member] |  |  |
Past due loans | $ 439,000 | $ 416,000 |

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