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Note 3 - Loans and Allowance for Credit Losses - Activity in Allowance for Loan Losses and the Recorded Investments in Loans (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Beginning balance |  | $ 35,363,000 | $ 37,967,000 |
Provision for credit losses |  | 100,000 | 300,000 |
Charge-offs |  | (205,000) | (52,000) |
Recoveries |  | 295,000 | 480,000 |
Ending balance |  | 35,153,000 | 38,695,000 |
Ending balance: individually evaluated for impairment |  |  | 487,000 |
Ending balance: collectively evaluated for impairment |  |  | 38,208,000 |
Ending balance | [1] |  |  | $ 3,413,349,000
Ending balance: individually evaluated for impairment | [1] |  |  | 19,366,000
Ending balance: collectively evaluated for impairment | [1] |  |  | 3,393,983,000
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (400,000) |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |
Beginning balance |  | 10,782,000 | 9,424,000 |
Provision for credit losses |  | (742,000) | 583,000 |
Charge-offs |  | (170,000) | 0 |
Recoveries |  | 114,000 | 104,000 |
Ending balance |  | 8,413,000 | 10,111,000 |
Ending balance: individually evaluated for impairment |  |  | 62,000 |
Ending balance: collectively evaluated for impairment |  |  | 10,049,000 |
Ending balance | [1] |  |  | 1,097,309,000
Ending balance: individually evaluated for impairment | [1] |  |  | 5,010,000
Ending balance: collectively evaluated for impairment | [1] |  |  | 1,092,299,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (1,571,000) |  |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |  |
Beginning balance |  | 420,000 | 679,000 |
Provision for credit losses |  | 106,000 | 40,000 |
Charge-offs |  | (29,000) | (15,000) |
Recoveries |  | 1,000 | 16,000 |
Ending balance |  | 455,000 | 720,000 |
Ending balance: individually evaluated for impairment |  |  | 0 |
Ending balance: collectively evaluated for impairment |  |  | 720,000 |
Ending balance |  |  |  | 43,239,000
Ending balance: individually evaluated for impairment |  |  |  | 0
Ending balance: collectively evaluated for impairment |  |  |  | 43,239,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (43,000) |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |  |
Beginning balance |  | 6,045,000 | 8,246,000 |
Provision for credit losses |  | 286,000 | (181,000) |
Charge-offs |  | 0 | 0 |
Recoveries |  | 32,000 | 239,000 |
Ending balance |  | 5,803,000 | 8,304,000 |
Ending balance: individually evaluated for impairment |  |  | 47,000 |
Ending balance: collectively evaluated for impairment |  |  | 8,257,000 |
Ending balance |  |  |  | 565,758,000
Ending balance: individually evaluated for impairment |  |  |  | 10,435,000
Ending balance: collectively evaluated for impairment |  |  |  | 555,323,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (560,000) |  |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |  |
Beginning balance |  | 13,301,000 | 13,611,000 |
Provision for credit losses |  | (445,000) | 140,000 |
Charge-offs |  | 0 | 0 |
Recoveries |  | 0 | 0 |
Ending balance |  | 10,322,000 | 13,751,000 |
Ending balance: individually evaluated for impairment |  |  | 7,000 |
Ending balance: collectively evaluated for impairment |  |  | 13,744,000 |
Ending balance |  |  |  | 1,027,415,000
Ending balance: individually evaluated for impairment |  |  |  | 146,000
Ending balance: collectively evaluated for impairment |  |  |  | 1,027,269,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (2,534,000) |  |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |  |
Beginning balance |  | 1,695,000 | 1,819,000 |
Provision for credit losses |  | 194,000 | 6,000 |
Charge-offs |  | 0 | 0 |
Recoveries |  | 8,000 | 0 |
Ending balance |  | 1,276,000 | 1,825,000 |
Ending balance: individually evaluated for impairment |  |  | 0 |
Ending balance: collectively evaluated for impairment |  |  | 1,825,000 |
Ending balance |  |  |  | 176,593,000
Ending balance: individually evaluated for impairment |  |  |  | 91,000
Ending balance: collectively evaluated for impairment |  |  |  | 176,502,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (621,000) |  |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |  |
Beginning balance |  | 2,449,000 | 3,240,000 |
Provision for credit losses |  | 593,000 | (337,000) |
Charge-offs |  | (2,000) | (33,000) |
Recoveries |  | 127,000 | 83,000 |
Ending balance |  | 8,562,000 | 2,953,000 |
Ending balance: individually evaluated for impairment |  |  | 141,000 |
Ending balance: collectively evaluated for impairment |  |  | 2,812,000 |
Ending balance |  |  |  | 442,547,000
Ending balance: individually evaluated for impairment |  |  |  | 2,437,000
Ending balance: collectively evaluated for impairment |  |  |  | 440,110,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | 5,395,000 |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |  |
Beginning balance |  | 626,000 | 889,000 |
Provision for credit losses |  | (33,000) | (82,000) |
Charge-offs |  | (4,000) | (4,000) |
Recoveries |  | 13,000 | 38,000 |
Ending balance |  | 191,000 | 841,000 |
Ending balance: individually evaluated for impairment |  |  | 230,000 |
Ending balance: collectively evaluated for impairment |  |  | 611,000 |
Ending balance |  |  |  | 60,488,000
Ending balance: individually evaluated for impairment |  |  |  | 1,247,000
Ending balance: collectively evaluated for impairment |  |  |  | $ 59,241,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | (411,000) |  |
Unallocated Financing Receivables [Member] |  |  |  |
Beginning balance |  | 45,000 | 59,000 |
Provision for credit losses |  | 141,000 | 131,000 |
Charge-offs |  | 0 | 0 |
Recoveries |  | 0 | 0 |
Ending balance |  | 131,000 | 190,000 |
Ending balance: individually evaluated for impairment |  |  | 0 |
Ending balance: collectively evaluated for impairment |  |  | $ 190,000 |
Unallocated Financing Receivables [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Beginning balance |  | $ (55,000) |  |
[1] | Excludes $40.1 million in loans originated under the Paycheck Protection Program.

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