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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, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Provision for loan losses | $ 900,000 | $ 700,000 | $ 1,750,000 | $ 700,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,881,493,000 |  | 2,881,493,000 |  | $ 2,753,085,000
Originated Loan [Member] |  |  |  |  |
Beginning balance | 22,418,000 | 19,081,000 | 21,554,000 | 19,133,000 |
Provision for loan losses | 898,000 | 914,000 | 1,867,000 | 132,000 |
Charge-offs | (77,000) | (274,000) | (252,000) | (666,000) |
Recoveries | 92,000 | 761,000 | 162,000 | 1,883,000 |
Ending balance | 23,331,000 | 20,482,000 | 23,331,000 | 20,482,000 |
Ending balance: individually evaluated for impairment | 2,227,000 | 674,000 | 2,227,000 | 674,000 |
Ending balance: collectively evaluated for impairment | 21,104,000 | 19,808,000 | 21,104,000 | 19,808,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,609,686,000 |  | 2,609,686,000 |  | 2,452,446,000
Ending balance: individually evaluated for impairment | 27,785,000 |  | 27,785,000 |  | 18,882,000
Ending balance: collectively evaluated for impairment | 2,581,901,000 |  | 2,581,901,000 |  | 2,433,564,000
Acquired Loan [Member] |  |  |  |  |
Beginning balance | 717,000 | 893,000 | 826,000 | 368,000 |
Provision for loan losses | 2,000 | (214,000) | (117,000) | 568,000 |
Charge-offs | 0 | 0 | 0 | (261,000) |
Recoveries | 3,000 | 6,000 | 13,000 | 10,000 |
Ending balance | 722,000 | 685,000 | 722,000 | 685,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 271,807,000 |  | 271,807,000 |  | 300,639,000
Commercial Portfolio Segment [Member] |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,464,555,000 |  | 2,464,555,000 |  | 2,360,106,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |  |  |
Beginning balance | 20,050,000 | 16,865,000 | 19,442,000 | 16,456,000 |
Provision for loan losses | 979,000 | 892,000 | 1,559,000 | 551,000 |
Charge-offs | (2,000) | (85,000) | (2,000) | (342,000) |
Recoveries | 46,000 | 654,000 | 74,000 | 1,661,000 |
Ending balance | 21,073,000 | 18,326,000 | 21,073,000 | 18,326,000 |
Ending balance: individually evaluated for impairment | 2,051,000 | 391,000 | 2,051,000 | 391,000 |
Ending balance: collectively evaluated for impairment | 19,022,000 | 17,935,000 | 19,022,000 | 17,935,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,274,931,000 |  | 2,274,931,000 |  | 2,151,998,000
Ending balance: individually evaluated for impairment | 25,936,000 |  | 25,936,000 |  | 17,134,000
Ending balance: collectively evaluated for impairment | 2,248,995,000 |  | 2,248,995,000 |  | 2,134,864,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |  |  |
Beginning balance | 161,000 | 359,000 | 177,000 | 291,000 |
Provision for loan losses | 36,000 | (254,000) | 20,000 | 60,000 |
Charge-offs | 0 | 0 | 0 | (246,000) |
Recoveries | 1,000 | 0 | 1,000 | 0 |
Ending balance | 198,000 | 105,000 | 198,000 | 105,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 189,624,000 |  | 189,624,000 |  | 208,108,000
Retail Portfolio Segment [Member] |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 416,938,000 |  | 416,938,000 |  | 392,979,000
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |  |  |
Beginning balance | 2,140,000 | 2,001,000 | 2,068,000 | 2,584,000 |
Provision for loan losses | 50,000 | 297,000 | 255,000 | (266,000) |
Charge-offs | (75,000) | (189,000) | (250,000) | (324,000) |
Recoveries | 46,000 | 107,000 | 88,000 | 222,000 |
Ending balance | 2,161,000 | 2,216,000 | 2,161,000 | 2,216,000 |
Ending balance: individually evaluated for impairment | 176,000 | 283,000 | 176,000 | 283,000 |
Ending balance: collectively evaluated for impairment | 1,985,000 | 1,933,000 | 1,985,000 | 1,933,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 334,755,000 |  | 334,755,000 |  | 300,448,000
Ending balance: individually evaluated for impairment | 1,849,000 |  | 1,849,000 |  | 1,748,000
Ending balance: collectively evaluated for impairment | 332,906,000 |  | 332,906,000 |  | 298,700,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |  |  |
Beginning balance | 556,000 | 534,000 | 649,000 | 77,000 |
Provision for loan losses | (34,000) | 40,000 | (137,000) | 508,000 |
Charge-offs | 0 | 0 | 0 | (15,000) |
Recoveries | 2,000 | 6,000 | 12,000 | 10,000 |
Ending balance | 524,000 | 580,000 | 524,000 | 580,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 82,183,000 |  | 82,183,000 |  | $ 92,531,000
Unallocated Financing Receivables [Member] | Originated Loan [Member] |  |  |  |  |
Beginning balance | 228,000 | 215,000 | 44,000 | 93,000 |
Provision for loan losses | (131,000) | (275,000) | 53,000 | (153,000) |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Ending balance | 97,000 | (60,000) | 97,000 | (60,000) |
Ending balance: individually evaluated for impairment | 0 | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | 97,000 | (60,000) | 97,000 | (60,000) |
Loans and Leases Receivable, Net of Deferred Income, Total |  |  |  |  |
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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