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Note 7 - Deposits (Tables) | 12 Months Ended
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Dec. 31, 2020
Notes Tables |
Summary of Deposits and Percentage Change in Deposits [Table Text Block] |
|  | December 31, 2020 |  |  | December 31, 2019 |  |  | Percent Increase |
|  | Balance |  |  | % |  |  | Balance |  |  | % |  |  | (Decrease) |
Noninterest-bearing checking |  | $ | 1,433,403,000 |  |  |  | 42.0 | % |  | $ | 924,916,000 |  |  |  | 34.4 | % |  |  | 55.0 | %
Interest-bearing checking |  |  | 473,053,000 |  |  |  | 13.9 |  |  |  | 332,373,000 |  |  |  | 12.3 |  |  |  | 42.3 |
Money market |  |  | 611,912,000 |  |  |  | 17.9 |  |  |  | 509,368,000 |  |  |  | 18.9 |  |  |  | 20.1 |
Savings |  |  | 338,070,000 |  |  |  | 9.9 |  |  |  | 269,318,000 |  |  |  | 10.0 |  |  |  | 25.5 |
Time, under $100,000 |  |  | 165,548,000 |  |  |  | 4.9 |  |  |  | 198,123,000 |  |  |  | 7.4 |  |  |  | (16.4 | )
Time, $100,000 and over |  |  | 342,633,000 |  |  |  | 10.0 |  |  |  | 322,827,000 |  |  |  | 12.0 |  |  |  | 6.1 |
Total local deposits |  |  | 3,364,619,000 |  |  |  | 98.6 |  |  |  | 2,556,925,000 |  |  |  | 95.0 |  |  |  | 31.6 |
Out-of-area time, $100,000 and over |  |  | 46,934,000 |  |  |  | 1.4 |  |  |  | 133,459,000 |  |  |  | 5.0 |  |  |  | (64.8 | )
Total deposits |  | $ | 3,411,553,000 |  |  |  | 100.0 | % |  | $ | 2,690,384,000 |  |  |  | 100.0 | % |  |  | 26.8 | %
Contractual Maturities of Certificates of Deposits [Table Text Block] |
|  | 2020 |  |  | 2019 |
In one year or less |  | $ | 327,246,000 |  |  | $ | 360,395,000 |
In one to two years |  |  | 139,801,000 |  |  |  | 173,512,000 |
In two to three years |  |  | 39,801,000 |  |  |  | 82,480,000 |
In three to four years |  |  | 25,577,000 |  |  |  | 16,019,000 |
In four to five years |  |  | 22,690,000 |  |  |  | 22,003,000 |
Total certificates of deposit |  | $ | 555,115,000 |  |  | $ | 654,409,000 |
Contractual Maturities of Certificates of Deposits of More than Specified Amount [Table Text Block] |
|  | 2020 |  |  | 2019 |
Up to three months |  | $ | 79,500,000 |  |  | $ | 100,635,000 |
Three months to six months |  |  | 79,373,000 |  |  |  | 59,838,000 |
Six months to twelve months |  |  | 77,363,000 |  |  |  | 93,691,000 |
Over twelve months |  |  | 153,331,000 |  |  |  | 202,122,000 |
Total certificates of deposit |  | $ | 389,567,000 |  |  | $ | 456,286,000 |

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