| **Derivatives (Tables)**                                                               | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Derivative Instruments and Hedging Activities Disclosure [Abstract]**                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Credit Value Adjustment Recorded Related to Notional Amount of Derivatives Outstanding | The following table depicts the credit value adjustment recorded related to the notional amount of derivatives outstanding as well as the notional amount of risk participation agreements participated to other banks at December 31: 2013 2012 (dollars in thousands)Credit value adjustment$77 $(2,207)Notional Amount:   Interest rate derivatives274,718 223,448Interest rate caps7,500 —Risk participation agreements82,197 71,390Sold credit protection on risk participation agreements(19,161) — |
| Schedule of Change in Fair Value of Derivative Assets and Liabilities                  | The table below presents the amount representing the change in the fair value of derivative assets and derivative liabilities attributable to credit risk included in “Other income” on the Consolidated Statements of Income for the years ended December 31: 2013 2012 2011 (dollars in thousands)Non-hedging interest rate derivatives:     Increase (decrease) in other income$1,428 $755 $(6,687)                                                                                                    |

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| - Definition
Notional amounts and credit value adjustment recorded related to the notional amount of derivatives outstanding.
+ References
No definition available.
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| - Definition
Tabular disclosure of interest rate derivatives, including, but not limited to, the fair value of the derivatives, statement of financial position location, and statement of financial performance location of these instruments.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959
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