| **Committments and Contingent Liabilities (Details) (USD $)In Thousands, unless otherwise specified** | Dec. 31, 2012 | Dec. 31, 2011 |
|-------------------------------------------------------------------------------------------------------|---------------|---------------|
| Loan Commitments to Extend Credit                                                                     |          |          |
| **Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]**                          |          |          |
| Amounts of committments                                                                               | $ 873,455     | $ 619,901     |
| Standby Letters of Credit                                                                             |          |          |
| **Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]**                          |          |          |
| Amounts of committments                                                                               | $ 21,734      | $ 28,665      |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611
+ Details**Name:**us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountLiability**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |