|**Deposits (Tables)**                                                    | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                
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|**Banking and Thrift [Abstract]**                                        |                                                                                                                                                                                                                                                                                                                                                                                                
|Schedule Of Deposits                                                     | The composition of the deposit portfolio is included in the table below for the years indicated:December 31, 2014December 31, 2013Demand deposits$2,146,492$2,018,650Savings deposits1,376,7071,257,994Certificates and other time deposits of $100,000 or more260,685272,660Other certificates and time deposits523,010595,110Brokered deposits333,80087,054Total deposits$4,640,694$4,231,468
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|                                                                         | December 31, 2014                                                                                                                                                                                                                                                                                                                                                                              
|Demand deposits                                                          | $                                                                                                                                                                                                                                                                                                                                                                                              
|Savings deposits                                                         | 1,376,707                                                                                                                                                                                                                                                                                                                                                                                      
|Certificates and other time deposits of $100,000 or more                 | 260,685                                                                                                                                                                                                                                                                                                                                                                                        
|Other certificates and time deposits                                     | 523,010                                                                                                                                                                                                                                                                                                                                                                                        
|Brokered deposits                                                        | 333,800                                                                                                                                                                                                                                                                                                                                                                                        
|Total deposits                                                           | $                                                                                                                                                                                                                                                                                                                                                                                              
|Schedule of Deposit Contractual Maturities, Excluding Demand and Savings | At December 31, 2014, the contractual maturities of time deposits are summarized as follows:Certificates and Other Time Deposits2015$469,3522016256,9212017144,348201887,234201952,792After 2019106,848$1,117,495                                                                                                                                                                              
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|                                                                         | Certificates and Other Time Deposits                                                                                                                                                                                                                                                                                                                                                           
|2015                                                                     | $                                                                                                                                                                                                                                                                                                                                                                                              
|2016                                                                     | 256,921                                                                                                                                                                                                                                                                                                                                                                                        
|2017                                                                     | 144,348                                                                                                                                                                                                                                                                                                                                                                                        
|2018                                                                     | 87,234                                                                                                                                                                                                                                                                                                                                                                                         
|2019                                                                     | 52,792                                                                                                                                                                                                                                                                                                                                                                                         
|After 2019                                                               | 106,848                                                                                                                                                                                                                                                                                                                                                                                        
|                                                                         | $                                                                                                                                                                                                                                                                                                                                                                                              

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