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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 |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Provision for loan losses | $ 850,000 | $ 0 |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,799,639,000 |  | $ 2,753,085,000
Originated Loan [Member] |  |  |
Beginning balance | 21,554,000 | 19,133,000 |
Provision for loan losses | 969,000 | (782,000) |
Charge-offs | (174,000) | (393,000) |
Recoveries | 69,000 | 1,123,000 |
Ending balance | 22,418,000 | 19,081,000 |
Ending balance: individually evaluated for impairment | 1,046,000 | 863,000 |
Ending balance: collectively evaluated for impairment | 21,372,000 | 18,218,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,511,036,000 |  | 2,452,446,000
Ending balance: individually evaluated for impairment | 20,191,000 |  | 18,882,000
Ending balance: collectively evaluated for impairment | 2,490,845,000 |  | 2,433,564,000
Acquired Loan [Member] |  |  |
Beginning balance | 826,000 | 368,000 |
Provision for loan losses | (119,000) | 782,000 |
Charge-offs | 0 | (261,000) |
Recoveries | 10,000 | 4,000 |
Ending balance | 717,000 | 893,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 288,603,000 |  | 300,639,000
Commercial Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,400,198,000 |  | 2,360,106,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Beginning balance | 19,442,000 | 16,456,000 |
Provision for loan losses | 578,000 | (341,000) |
Charge-offs | 0 | (258,000) |
Recoveries | 30,000 | 1,008,000 |
Ending balance | 20,050,000 | 16,865,000 |
Ending balance: individually evaluated for impairment | 855,000 | 547,000 |
Ending balance: collectively evaluated for impairment | 19,195,000 | 16,318,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,198,713,000 |  | 2,151,998,000
Ending balance: individually evaluated for impairment | 18,503,000 |  | 17,134,000
Ending balance: collectively evaluated for impairment | 2,180,210,000 |  | 2,134,864,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Beginning balance | 177,000 | 291,000 |
Provision for loan losses | (16,000) | 314,000 |
Charge-offs | 0 | (246,000) |
Recoveries | 0 | 0 |
Ending balance | 161,000 | 359,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 201,485,000 |  | 208,108,000
Retail Portfolio Segment [Member] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 399,441,000 |  | 392,979,000
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Beginning balance | 2,068,000 | 2,584,000 |
Provision for loan losses | 207,000 | (563,000) |
Charge-offs | (174,000) | (135,000) |
Recoveries | 39,000 | 115,000 |
Ending balance | 2,140,000 | 2,001,000 |
Ending balance: individually evaluated for impairment | 191,000 | 316,000 |
Ending balance: collectively evaluated for impairment | 1,949,000 | 1,685,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 312,323,000 |  | 300,448,000
Ending balance: individually evaluated for impairment | 1,688,000 |  | 1,748,000
Ending balance: collectively evaluated for impairment | 310,635,000 |  | 298,700,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Beginning balance | 649,000 | 77,000 |
Provision for loan losses | (103,000) | 468,000 |
Charge-offs | 0 | (15,000) |
Recoveries | 10,000 | 4,000 |
Ending balance | 556,000 | 534,000 |
Loans and Leases Receivable, Net of Deferred Income, Total | 87,118,000 |  | $ 92,531,000
Unallocated Financing Receivables [Member] | Originated Loan [Member] |  |  |
Beginning balance | 44,000 | 93,000 |
Provision for loan losses | 184,000 | 122,000 |
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
Ending balance | 228,000 | 215,000 |
Ending balance: individually evaluated for impairment | 0 | 0 |
Ending balance: collectively evaluated for impairment | 228,000 | 215,000 |
Unallocated Financing Receivables [Member] | Acquired Loan [Member] |  |  |
Beginning balance | 0 | 0 |
Provision for loan losses | 0 | 0 |
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
Ending balance | $ 0 | $ 0 |

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