|**Loans (Impaired Loans) (Details) (USD $)**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
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|**Financing Receivable, Impaired [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Impaired loans, no individually reviewed for impairment                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | $ 9,313,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Impaired loans, individually reviewed, with no impairment                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | 51,557,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Impaired loans, individually reviewed, with impairment                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | 5,935,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Total impaired loans, excluding purchased impaired                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | 66,805,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | [1]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Purchased impaired loans with subsequent deterioration                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | 161,278,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Purchased impaired loans with no subsequent deterioration                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | 27,881,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Impaired loan, individually reviewed, with impairment, associated reserves                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   | 763,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | [1]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Purchased impaired loans with subsequent deterioration, associated reserves                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | 4,066,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Impaired financing receivable, including deteriorated loans purchased, related allowance                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | 4,829,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Imparied financing receivable, simple average balance                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 72,917,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Restructured loans                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | 16,300,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Performing [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|**Financing Receivable, Impaired [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Restructured loans                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | $ 4,300,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
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|[1]
              June 30, 2013 December 31, 2012(dollars in thousands) BalanceAssociated Reserves BalanceAssociated ReservesImpaired loans, not individually reviewed for impairment $9,313$— $6,017$—Impaired loans, individually reviewed, with no impairment 51,557— 62,282—Impaired loans, individually reviewed, with impairment 5,935763 15,3121,737Total impaired loans, excluding purchased impaired * $66,805$763 $83,611$1,737 Purchased impaired loans with subsequent deterioration $161,2784,066 $192,1155,373Purchased impaired loans with no subsequent deterioration $27,881— $36,277—Total Reserves $4,829 $7,110 Average impaired loans calculated using a simple average $72,917 $94,754 | [1]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | June 30, 2013 December 31, 2012(dollars in thousands) BalanceAssociated Reserves BalanceAssociated ReservesImpaired loans, not individually reviewed for impairment $9,313$— $6,017$—Impaired loans, individually reviewed, with no impairment 51,557— 62,282—Impaired loans, individually reviewed, with impairment 5,935763 15,3121,737Total impaired loans, excluding purchased impaired * $66,805$763 $83,611$1,737 Purchased impaired loans with subsequent deterioration $161,2784,066 $192,1155,373Purchased impaired loans with no subsequent deterioration $27,881— $36,277—Total Reserves $4,829 $7,110 Average impaired loans calculated using a simple average $72,917 $94,754
|[1]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | June 30, 2013 December 31, 2012(dollars in thousands) BalanceAssociated Reserves BalanceAssociated ReservesImpaired loans, not individually reviewed for impairment $9,313$— $6,017$—Impaired loans, individually reviewed, with no impairment 51,557— 62,282—Impaired loans, individually reviewed, with impairment 5,935763 15,3121,737Total impaired loans, excluding purchased impaired * $66,805$763 $83,611$1,737 Purchased impaired loans with subsequent deterioration $161,2784,066 $192,1155,373Purchased impaired loans with no subsequent deterioration $27,881— $36,277—Total Reserves $4,829 $7,110 Average impaired loans calculated using a simple average $72,917 $94,754

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