| **Supplemental Cash Flow Disclosures (Tables)**   | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Supplemental Cash Flow Information [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Schedule of Supplemental Cash Flow Disclosures    | The following table presents information related to cash paid during the period for interest, as well as detail on non-cash investing and financing activities for the nine months endedSeptember 30: 2016 2015 (dollars in thousands)Cash paid during the period for:   Interest$14,768 $11,682Income taxes15,750 4,000Non-cash investing and financing activities:   Loans transferred to other real estate owned and repossessed assets3,973 7,413Loans transferred from held to maturity to held for sale3,573 3,071Gross increase in market value adjustment to securities available for sale13,094 12,381Gross increase in market value adjustment to derivatives981 2,167Investments committed to purchase, not settled276 1,350Proceeds from death benefit on bank-owned life insurance not received320 — |

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Tabular disclosure of supplemental cash flow information for the periods presented.
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No definition available.
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