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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 ($) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Beginning balance |  | $ 23,889,000 | $ 22,380,000 | $ 19,501,000 |  |  |  |
Provision for loan losses |  | 14,050,000 | 1,750,000 | 1,100,000 |  |  |  |
Charge-offs |  | (838,000) | (883,000) | (1,450,000) |  |  |  |
Recoveries |  | 866,000 | 642,000 | 3,229,000 |  |  |  |
Ending balance |  | 37,967,000 | 23,889,000 | 22,380,000 |  |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | $ 551,000 |  | $ 1,689,000 | $ 1,089,000
Ending balance: collectively evaluated for impairment |  |  |  |  | 37,416,000 |  | 22,200,000 | 21,291,000
Ending balance | [1] |  |  |  | 2,851,099,000 |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | 26,958,000 | [1] | 14,622,000 | 23,908,000
Ending balance: collectively evaluated for impairment |  |  |  |  | 2,824,141,000 | [1] | 2,842,045,000 | 2,729,177,000
Loans and Leases Receivable, Net of Deferred Income, Total |  | 3,216,358,000 | 2,856,667,000 | 2,753,085,000 | 3,216,358,000 |  | 2,856,667,000 | 2,753,085,000
Ending balance |  | 3,216,358,000 | 2,856,667,000 | 2,753,085,000 |  |  |  |
Commercial Portfolio Segment [Member] |  |  |  |  |  |  |  |
Beginning balance |  | 21,070,000 | 19,619,000 | 16,747,000 |  |  |  |
Provision for loan losses |  | 12,835,000 | 1,578,000 | 958,000 |  |  |  |
Charge-offs |  | (613,000) | (455,000) | (674,000) |  |  |  |
Recoveries |  | 487,000 | 328,000 | 2,588,000 |  |  |  |
Ending balance |  | 33,779,000 | 21,070,000 | 19,619,000 |  |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | 138,000 |  | 1,230,000 | 550,000
Ending balance: collectively evaluated for impairment |  |  |  |  | 33,641,000 |  | 19,840,000 | 19,069,000
Ending balance | [1] |  |  |  | 2,428,703,000 |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | 22,415,000 | [1] | 10,604,000 | 19,291,000
Ending balance: collectively evaluated for impairment |  |  |  |  | 2,406,288,000 | [1] | 2,430,940,000 | 2,340,815,000
Loans and Leases Receivable, Net of Deferred Income, Total |  | 2,793,962,000 | 2,441,544,000 | 2,360,106,000 | 2,793,962,000 |  | 2,441,544,000 | 2,360,106,000
Ending balance |  | 2,793,962,000 | 2,441,544,000 | 2,360,106,000 |  |  |  |
Retail Portfolio Segment [Member] |  |  |  |  |  |  |  |
Beginning balance |  | 2,749,000 | 2,717,000 | 2,661,000 |  |  |  |
Provision for loan losses |  | 1,226,000 | 146,000 | 191,000 |  |  |  |
Charge-offs |  | (225,000) | (428,000) | (776,000) |  |  |  |
Recoveries |  | 379,000 | 314,000 | 641,000 |  |  |  |
Ending balance |  | 4,129,000 | 2,749,000 | 2,717,000 |  |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | 413,000 |  | 459,000 | 539,000
Ending balance: collectively evaluated for impairment |  |  |  |  | 3,716,000 |  | 2,290,000 | 2,178,000
Ending balance | [1] |  |  |  | 422,396,000 |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | 4,543,000 | [1] | 4,018,000 | 4,617,000
Ending balance: collectively evaluated for impairment |  |  |  |  | 417,853,000 | [1] | 411,105,000 | 388,362,000
Loans and Leases Receivable, Net of Deferred Income, Total |  | 422,396,000 | 415,123,000 | 392,979,000 | 422,396,000 |  | 415,123,000 | 392,979,000
Ending balance |  | 422,396,000 | 415,123,000 | 392,979,000 |  |  |  |
Unallocated Financing Receivables [Member] |  |  |  |  |  |  |  |
Beginning balance |  | 70,000 | 44,000 | 93,000 |  |  |  |
Provision for loan losses |  | (11,000) | 26,000 | (49,000) |  |  |  |
Charge-offs |  | 0 | 0 | 0 |  |  |  |
Recoveries |  | 0 | 0 | 0 |  |  |  |
Ending balance |  | $ 59,000 | $ 70,000 | $ 44,000 |  |  |  |
Ending balance: individually evaluated for impairment |  |  |  |  | 0 |  | 0 | 0
Ending balance: collectively evaluated for impairment |  |  |  |  | $ 59,000 |  | $ 70,000 | $ 44,000
[1] | Excludes $365 million in loans originated under the Paycheck Protection Program.

X
- 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 and Paycheck Protection Program loans. + References No definition available. + Details
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