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Borrowed Funds (Borrowed funds obligations) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017
Schedule of Debt [Line Items] |  |  |  |  |
Borrowed funds | $ 362,496 |  | $ 362,496 |  | $ 344,878
Borrowed funds, Rate | 1.92% |  | 1.92% |  | 1.65%
Securities Sold under Agreements to Repurchase [Member] |  |  |  |  |
Schedule of Debt [Line Items] |  |  |  |  |
Short-term Debt, Maximum Month-end Outstanding Amount | $ 34,242 | $ 55,731 | $ 38,967 | $ 61,131 |
Borrowed funds | $ 31,296 |  | $ 31,296 |  | $ 54,878
Borrowed funds, Rate | 0.10% |  | 0.10% |  | 0.12%
Federal Funds Purchased [Member] |  |  |  |  |
Schedule of Debt [Line Items] |  |  |  |  |
Short-term Debt, Maximum Month-end Outstanding Amount | $ 16,200 | $ 5,965 | $ 16,200 | $ 27,300 |
Borrowed funds | $ 16,200 |  | $ 16,200 |  | $ 0
Borrowed funds, Rate | 2.14% |  | 2.14% |  | 0.00%
Federal Home Loan Bank Advances [Member] |  |  |  |  |
Schedule of Debt [Line Items] |  |  |  |  |
Borrowed funds | $ 315,000 |  | $ 315,000 |  | $ 290,000
Borrowed funds, Rate | 2.09% |  | 2.09% |  | 1.94%

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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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