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Other Intangible Assets and Goodwill (Tables) | 12 Months Ended
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Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract] |
Core deposit intangibles |
| At or for the Years ended
(Dollars in thousands) | December 31, 2013 |  | December 31, 2012 |  | December 31, 2011
Gross carrying value | $ | 27,857 |  |  | 22,404 |  |  | 28,248 |
Accumulated amortization | (18,345 | ) |  | (16,230 | ) |  | (19,964 | )
Net carrying value | $ | 9,512 |  |  | 6,174 |  |  | 8,284 |
Aggregate amortization expense | $ | 2,401 |  |  | 2,110 |  |  | 2,473 |
Weighted-average amortization period |  |  |  |  |
(Period in years) | 9.5 |  |  |  |  |
Estimated amortization expense for the years ending December 31, |  |  |  |  |
2014 | $ | 2,650 |  |  |  |  |
2015 | 2,198 |  |  |  |  |
2016 | 1,700 |  |  |  |  |
2017 | 828 |  |  |  |  |
2018 | 430 |  |  |  |  |
Changes in the carrying value of goodwill |
| Years ended
(Dollars in thousands) | December 31, 2013 |  | December 31, 2012 |  | December 31, 2011
Net carrying value at beginning of period | $ | 106,100 |  |  | 106,100 |  |  | 146,259 |
Acquisitions | 23,606 |  |  | — |  |  | — |
Impairment charge | — |  |  | — |  |  | (40,159 | )
Net carrying value at end of period | $ | 129,706 |  |  | 106,100 |  |  | 106,100 |
Gross carrying value of goodwill and the accumulated impairment charge |
(Dollars in thousands) | December 31, 2013 |  | December 31, 2012 |  |
Gross carrying value | $ | 169,865 |  |  | 146,259 |  |  |
Accumulated impairment charge | (40,159 | ) |  | (40,159 | ) |  |
Net carrying value | $ | 129,706 |  |  | 106,100 |  |  |

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- Definition Tabular disclosure of assets, excluding financial assets and goodwill, lacking physical substance with a finite life, by either major class or business segment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13854-109267 + Details
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