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Note 9 - Borrowed Funds (Tables) | 12 Months Ended
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Dec. 31, 2017
Notes Tables |
Summary of Comparative Data of Securities Sold under Agreements to Repurchase [Table Text Block] |
|  | 201 7 |  |  | 201 6 |  |  | 201 5 |
|  | (Dollars in thousands ) |
Average amount outstanding during the year (1) |  | $ | 136,849 |  |  | $ | 381,967 |  |  | $ | 400,822 |
Maximum amount outstanding at month-end (2) |  |  | 150,000 |  |  |  | 400,000 |  |  |  | 400,000 |
Balance, December 31 |  |  | 100,000 |  |  |  | 350,000 |  |  |  | 400,000 |
Rate, December 31 |  |  | 2.86 | % |  |  | 4.06 | % |  |  | 3.89 | %
Weighted average interest rate for the year |  |  | 3.11 | % |  |  | 4.01 | % |  |  | 3.95 | %

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