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Note 8 - Deposits (Tables) | 12 Months Ended
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Dec. 31, 2019
Notes Tables |
Summary of Deposits and Percentage Change in Deposits [Table Text Block] |
|  | December 31, 2019 |  |  | December 31, 2018 |  |  | Percent Increase |
|  | Balance |  |  | % |  |  | Balance |  |  | % |  |  | (Decrease) |
Noninterest-bearing demand |  | $ | 924,916,000 |  |  |  | 34.4 | % |  | $ | 889,784,000 |  |  |  | 36.1 | % |  |  | 3.9 | %
Interest-bearing checking |  |  | 332,373,000 |  |  |  | 12.3 |  |  |  | 339,089,000 |  |  |  | 13.8 |  |  |  | (2.0 | )
Money market |  |  | 509,368,000 |  |  |  | 18.9 |  |  |  | 434,333,000 |  |  |  | 17.6 |  |  |  | 17.3 |
Savings |  |  | 269,318,000 |  |  |  | 10.0 |  |  |  | 317,014,000 |  |  |  | 12.9 |  |  |  | (15.0 | )
Time, under $100,000 |  |  | 198,123,000 |  |  |  | 7.4 |  |  |  | 160,092,000 |  |  |  | 6.5 |  |  |  | 23.8 |
Time, $100,000 and over |  |  | 322,827,000 |  |  |  | 12.0 |  |  |  | 210,164,000 |  |  |  | 8.5 |  |  |  | 53.6 |
Total local deposits |  |  | 2,556,925,000 |  |  |  | 95.0 |  |  |  | 2,350,476,000 |  |  |  | 95.4 |  |  |  | 8.8 |
Out-of-area time, under $100,000 |  |  | 0 |  |  |  | 0.0 |  |  |  | 0 |  |  |  | 0.0 |  |  |  | 0.0 |
Out-of-area time, $100,000 and over |  |  | 133,459,000 |  |  |  | 5.0 |  |  |  | 113,232,000 |  |  |  | 4.6 |  |  |  | 17.9 |
Total out-of-area deposits |  |  | 133,459,000 |  |  |  | 5.0 |  |  |  | 113,232,000 |  |  |  | 4.6 |  |  |  | 17.9 |
Total deposits |  | $ | 2,690,384,000 |  |  |  | 100.0 | % |  | $ | 2,463,708,000 |  |  |  | 100.0 | % |  |  | 9.2 | %
Contractual Maturities of Certificates of Deposits [Table Text Block] |
|  | 2019 |  |  | 2018 |
In one year or less |  | $ | 360,395,000 |  |  | $ | 204,253,000 |
In one to two years |  |  | 173,512,000 |  |  |  | 167,484,000 |
In two to three years |  |  | 82,480,000 |  |  |  | 58,671,000 |
In three to four years |  |  | 16,019,000 |  |  |  | 36,690,000 |
In four to five years |  |  | 22,003,000 |  |  |  | 16,390,000 |
Total certificates of deposit |  | $ | 654,409,000 |  |  | $ | 483,488,000 |
Contractual Maturities of Certificates of Deposits of More than Specified Amount [Table Text Block] |
|  | 2019 |  |  | 2018 |
Up to three months |  | $ | 100,635,000 |  |  | $ | 34,367,000 |
Three months to six months |  |  | 59,838,000 |  |  |  | 41,939,000 |
Six months to twelve months |  |  | 93,691,000 |  |  |  | 57,137,000 |
Over twelve months |  |  | 202,122,000 |  |  |  | 189,953,000 |
Total certificates of deposit |  | $ | 456,286,000 |  |  | $ | 323,396,000 |

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