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Note 3 - Loans and Allowance for Loan Losses - Activity in Allowance for Loan Losses and the Recorded Investments in Loans (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017
Provision for loan losses | $ 700,000 | $ 750,000 | $ 700,000 | $ 1,350,000 |
Ending balance | 2,636,856,000 |  | 2,636,856,000 |  | $ 2,558,552,000
Originated Loan [Member] |  |  |  |  |
Beginning balance | 19,081,000 | 18,126,000 | 19,133,000 | 17,868,000 |
Provision for loan losses | 914,000 | 562,000 | 132,000 | 1,110,000 |
Charge-offs | (274,000) | (1,150,000) | (666,000) | (1,595,000) |
Recoveries | 761,000 | 417,000 | 1,883,000 | 572,000 |
Ending balance | 20,482,000 | 17,955,000 | 20,482,000 | 17,955,000 |
Ending balance: individually evaluated for impairment | 674,000 | 2,799,000 | 674,000 | 2,799,000 |
Ending balance: collectively evaluated for impairment | 19,808,000 | 15,156,000 | 19,808,000 | 15,156,000 |
Ending balance: individually evaluated for impairment | 6,658,000 |  | 6,658,000 |  | 8,787,000
Ending balance: collectively evaluated for impairment | 2,289,546,000 |  | 2,289,546,000 |  | 2,161,170,000
Ending balance | 2,296,204,000 |  | 2,296,204,000 |  | 2,169,957,000
Acquired Loan [Member] |  |  |  |  |
Beginning balance | 893,000 | 150,000 | 368,000 | 93,000 |
Provision for loan losses | (214,000) | 188,000 | 568,000 | 240,000 |
Charge-offs | 0 | 0 | (261,000) | (11,000) |
Recoveries | 6,000 | 2,000 | 10,000 | 18,000 |
Ending balance | 685,000 | 340,000 | 685,000 | 340,000 |
Ending balance | 340,652,000 |  | 340,652,000 |  | 388,595,000
Commercial Portfolio Segment [Member] |  |  |  |  |
Ending balance | 2,261,970,000 |  | 2,261,970,000 |  | 2,203,568,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |  |  |
Beginning balance | 16,865,000 | 15,671,000 | 16,456,000 | 16,026,000 |
Provision for loan losses | 892,000 | 372,000 | 551,000 | 147,000 |
Charge-offs | (85,000) | (1,006,000) | (342,000) | (1,231,000) |
Recoveries | 654,000 | 326,000 | 1,661,000 | 421,000 |
Ending balance | 18,326,000 | 15,363,000 | 18,326,000 | 15,363,000 |
Ending balance: individually evaluated for impairment | 391,000 | 2,044,000 | 391,000 | 2,044,000 |
Ending balance: collectively evaluated for impairment | 17,935,000 | 13,319,000 | 17,935,000 | 13,319,000 |
Ending balance: individually evaluated for impairment | 4,812,000 |  | 4,812,000 |  | 6,394,000
Ending balance: collectively evaluated for impairment | 2,022,381,000 |  | 2,022,381,000 |  | 1,927,834,000
Ending balance | 2,027,193,000 |  | 2,027,193,000 |  | 1,934,228,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |  |  |
Beginning balance | 359,000 | 125,000 | 291,000 | 75,000 |
Provision for loan losses | (254,000) | 197,000 | 60,000 | 242,000 |
Charge-offs | 0 | 0 | (246,000) | (11,000) |
Recoveries | 0 | 2,000 | 0 | 18,000 |
Ending balance | 105,000 | 324,000 | 105,000 | 324,000 |
Ending balance | 234,777,000 |  | 234,777,000 |  | 269,340,000
Retail Portfolio Segment [Member] |  |  |  |  |
Ending balance | 374,886,000 |  | 374,886,000 |  | 354,984,000
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |  |  |
Beginning balance | 2,001,000 | 2,365,000 | 2,584,000 | 1,882,000 |
Provision for loan losses | 297,000 | 121,000 | (266,000) | 764,000 |
Charge-offs | (189,000) | (144,000) | (324,000) | (364,000) |
Recoveries | 107,000 | 91,000 | 222,000 | 151,000 |
Ending balance | 2,216,000 | 2,433,000 | 2,216,000 | 2,433,000 |
Ending balance: individually evaluated for impairment | 283,000 | 755,000 | 283,000 | 755,000 |
Ending balance: collectively evaluated for impairment | 1,933,000 | 1,678,000 | 1,933,000 | 1,678,000 |
Ending balance: individually evaluated for impairment | 1,846,000 |  | 1,846,000 |  | 2,393,000
Ending balance: collectively evaluated for impairment | 267,165,000 |  | 267,165,000 |  | 233,336,000
Ending balance | 269,011,000 |  | 269,011,000 |  | 235,729,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |  |  |
Beginning balance | 534,000 | 25,000 | 77,000 | 18,000 |
Provision for loan losses | 40,000 | (9,000) | 508,000 | (2,000) |
Charge-offs | 0 | 0 | (15,000) | 0 |
Recoveries | 6,000 | 0 | 10,000 | 0 |
Ending balance | 580,000 | 16,000 | 580,000 | 16,000 |
Ending balance | 105,875,000 |  | 105,875,000 |  | $ 119,255,000
Unallocated Financing Receivables [Member] | Originated Loan [Member] |  |  |  |  |
Beginning balance | 215,000 | 90,000 | 93,000 | (40,000) |
Provision for loan losses | (275,000) | 69,000 | (153,000) | 199,000 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | (60,000) | 159,000 | (60,000) | 159,000 |
Ending balance: individually evaluated for impairment | 0 | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | (60,000) | 159,000 | (60,000) | 159,000 |
Unallocated Financing Receivables [Member] | Acquired Loan [Member] |  |  |  |  |
Beginning balance | 0 | 0 | 0 | 0 |
Provision for loan losses | 0 | 0 | 0 | 0 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | $ 0 | $ 0 | $ 0 | $ 0 |

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details
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