| Note 9 - Federal Funds Purchased | 12 Months Ended | ||
|---|---|---|---|
| Dec. 31, 2019 | |||
| Notes to Financial Statements | |||
| Federal Funds Purchased [Text Block] | 
 
 At December 31, 2019, the Company had $385.7 million in federal funds purchased from its correspondent banks that are clients of its correspondent banking unit, compared to $288.7 million at December 31, 2018. Rates paid on these funds were between 1.60% and 1.67% as of December 31, 2019 and 2.50% and 2.65% as of December 31, 2018. 
 At December 31, 2019, the Company had available lines of credit totaling approximately $767.0 million with various financial institutions for borrowing on a short-term basis, compared to $562.0 million at December 31, 2018. At December 31, 2019, the Company had $85.0 million in outstanding borrowings from these lines. The rate paid on this borrowing was 1.61%. The borrowing was paid off on January 2, 2020. | 
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- Definition The entire disclosure for purchase of federal funds during the period. No definition available. 
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- References No definition available. 
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