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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, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020 | [2]
Beginning balance | $ 38,695,000 |  | $ 24,828,000 | $ 37,967,000 |  | $ 23,889,000 |
Provision for loan losses | (3,100,000) |  | 7,600,000 | (2,800,000) |  | 8,350,000 |
Charge-offs | (68,000) |  | (335,000) | (121,000) |  | (375,000) |
Recoveries | 386,000 |  | 153,000 | 867,000 |  | 382,000 |
Ending balance | 35,913,000 |  | 32,246,000 | 35,913,000 |  | 32,246,000 |
Ending balance: individually evaluated for impairment | 787,000 |  | 1,512,000 | 787,000 |  | 1,512,000 |
Ending balance: collectively evaluated for impairment | 35,126,000 |  | 30,734,000 | 35,126,000 |  | 30,734,000 |
Ending balance | 3,003,058,000 | [1] |  | 3,003,058,000 | [1] |  | $ 2,828,211,000
Ending balance: individually evaluated for impairment | 23,915,000 |  |  | 23,915,000 |  |  | 26,958,000
Ending balance: collectively evaluated for impairment | 2,979,143,000 |  |  | 2,979,143,000 |  |  | 2,801,253,000
Commercial Portfolio Segment [Member] |  |  |  |  |  |  |
Beginning balance | 34,711,000 |  | 21,750,000 | 33,779,000 |  | 21,070,000 |
Provision for loan losses | (2,712,000) |  | 6,466,000 | (2,130,000) |  | 7,039,000 |
Charge-offs | (66,000) |  | (301,000) | (81,000) |  | (314,000) |
Recoveries | 159,000 |  | 47,000 | 524,000 |  | 167,000 |
Ending balance | 32,092,000 |  | 27,962,000 | 32,092,000 |  | 27,962,000 |
Ending balance: individually evaluated for impairment | 477,000 |  | 1,011,000 | 477,000 |  | 1,011,000 |
Ending balance: collectively evaluated for impairment | 31,615,000 |  | 26,951,000 | 31,615,000 |  | 26,951,000 |
Ending balance | 2,564,526,000 | [1] |  | 2,564,526,000 | [1] |  | 2,428,703,000
Ending balance: individually evaluated for impairment | 19,691,000 | [1] |  | 19,691,000 | [1] |  | 22,415,000
Ending balance: collectively evaluated for impairment | 2,544,835,000 | [1] |  | 2,544,835,000 | [1] |  | 2,406,288,000
Retail Portfolio Segment [Member] |  |  |  |  |  |  |
Beginning balance | 3,794,000 |  | 3,078,000 | 4,129,000 |  | 2,749,000 |
Provision for loan losses | (383,000) |  | 1,074,000 | (796,000) |  | 1,321,000 |
Charge-offs | (2,000) |  | (34,000) | (40,000) |  | (61,000) |
Recoveries | 227,000 |  | 106,000 | 343,000 |  | 215,000 |
Ending balance | 3,636,000 |  | 4,224,000 | 3,636,000 |  | 4,224,000 |
Ending balance: individually evaluated for impairment | 310,000 |  | 501,000 | 310,000 |  | 501,000 |
Ending balance: collectively evaluated for impairment | 3,326,000 |  | 3,723,000 | 3,326,000 |  | 3,723,000 |
Ending balance | 438,532,000 | [1] |  | 438,532,000 | [1] |  | 399,508,000
Ending balance: individually evaluated for impairment | 4,224,000 |  |  | 4,224,000 |  |  | 4,543,000
Ending balance: collectively evaluated for impairment | 434,308,000 |  |  | 434,308,000 |  |  | $ 394,965,000
Unallocated Financing Receivables [Member] |  |  |  |  |  |  |
Beginning balance | 190,000 |  | 0 | 59,000 |  | 70,000 |
Provision for loan losses | (5,000) |  | 60,000 | 126,000 |  | (10,000) |
Charge-offs | 0 |  | 0 | 0 |  | 0 |
Recoveries | 0 |  | 0 | 0 |  | 0 |
Ending balance | 185,000 |  | 60,000 | 185,000 |  | 60,000 |
Ending balance: individually evaluated for impairment | 0 |  | 0 | 0 |  | 0 |
Ending balance: collectively evaluated for impairment | $ 185,000 |  | $ 60,000 | $ 185,000 |  | $ 60,000 |
[1] | Excludes $246 million in loans originated under the Paycheck Protection Program.
[2] | Excludes $365 million in loans originated under the Paycheck Protection Program.

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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 and Paycheck Protection Program loans. + References No definition available. + Details
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- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (3) Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (c) Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (1) + Details
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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
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- Definition Amount of increase in allowance for credit loss on financing receivable from recovery. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
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