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Borrowed Funds (Short-term borrowings) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Securities Sold under Agreements to Repurchase [Member] |  |  |  |
Short-term Debt [Line Items] |  |  |  |
Maximum Month End Balance | $ 34,242 | $ 55,731 | $ 38,967 | $ 61,131
Average Balance | $ 32,957 | $ 53,841 | $ 34,467 | $ 55,663
Weighted Average Interest Rate During the Period | 0.09% | 0.13% | 0.09% | 0.13%
Federal Funds Purchased [Member] |  |  |  |
Short-term Debt [Line Items] |  |  |  |
Maximum Month End Balance | $ 16,200 | $ 5,965 | $ 16,200 | $ 27,300
Average Balance | $ 9,199 | $ 7,496 | $ 6,843 | $ 4,197
Weighted Average Interest Rate During the Period | 1.82% | 1.13% | 1.77% | 1.11%
Federal Reserve Bank Advances [Member] |  |  |  |
Short-term Debt [Line Items] |  |  |  |
Maximum Month End Balance | $ 0 | $ 0 | $ 0 | $ 0
Average Balance | $ 0 | $ 88 | $ 0 | $ 44
Weighted Average Interest Rate During the Period | 0.00% | 1.48% | 0.00% | 1.48%

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- Definition For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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