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Borrowed Funds (Short-term borrowings) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Securities Sold under Agreements to Repurchase [Member] |  |
Short-term Debt [Line Items] |  |
Maximum Month End Balance | $ 38,967 | $ 58,088
Average Balance | $ 35,995 | $ 57,505
Weighted Average Interest Rate During the Period | 0.10% | 0.13%
Federal Funds Purchased [Member] |  |
Short-term Debt [Line Items] |  |
Maximum Month End Balance | $ 10,200 | $ 5,200
Average Balance | $ 4,460 | $ 863
Weighted Average Interest Rate During the Period | 1.66% | 0.96%

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