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Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 | Dec. 23, 2015 | Dec. 31, 2014
Commitments and Contingent Liabilities [Abstract] |  |  |
Percentage of the Company's loans secured by real estate | 58.00% |  |
Guarantor Obligations [Line Items] |  |  |
Loans serviced by the Company for unrelated third parties | $ 616,100 |  | $ 626,000
Mortgage servicing rights | $ 1,100 |  | 1,500
Federal Reserve Bank Requirement [Abstract] |  |  |
Federal Reserve Bank maintenance period | 14 days |  |
Average reserve at Federal Reserve Bank for maintenance period |  | $ 55,800 |
Unused lines of Credit [Member] |  |  |
Guarantor Obligations [Line Items] |  |  |
Commitments - maximum potential obligation | $ 252,953 |  | 214,175
Commitment to Extend Credits, Primarily Variable Rate [Member] |  |  |
Guarantor Obligations [Line Items] |  |  |
Commitments - maximum potential obligation | 1,062,425 |  | 972,912
Standby Letters of Credit [Member] |  |  |
Guarantor Obligations [Line Items] |  |  |
Commitments - maximum potential obligation | $ 31,503 |  | 35,244
Obligation instrument term | 5 years |  |
Commercial Letters of Credit [Member] |  |  |
Guarantor Obligations [Line Items] |  |  |
Commitments - maximum potential obligation | $ 11,332 |  | 22,486
Loans Sold with Recourse [Member] |  |  |
Guarantor Obligations [Line Items] |  |  |
Commitments - maximum potential obligation | $ 25,122 |  | $ 23,351

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