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Goodwill and Other Intangible Assets (Tables) | 12 Months Ended
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Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract] |
Goodwill | The following table presents goodwill as of the dates presented:
| December 31,
(dollars in thousands) | 2016 |  | 2015
Balance at beginning of year | $ | 291,764 |  |  | $ | 175,820 |
Additions | — |  |  | 115,944 |
Other adjustments | (94 | ) |  | — |
Balance at End of Year | $ | 291,670 |  |  | $ | 291,764 |
Summary of Intangible Assets | The following table shows a summary of intangible assets as of the dates presented:
| December 31,
(dollars in thousands) | 2016 |  | 2015
Gross carrying amount at beginning of year | $ | 22,114 |  |  | $ | 16,401 |
Additions | — |  |  | 5,713 |
Accumulated amortization | (17,204 | ) |  | (15,589 | )
Balance at End of Year | $ | 4,910 |  |  | $ | 6,525 |
Summary of Expected Amortization Expense for Finite-Lived Intangibles Assets | The following is a summary of the expected amortization expense for finite-lived intangible assets, assuming no new additions, for each of the five years following December 31, 2016:
(dollars in thousands) | Amount |
2017 | $ | 1,311 |
2018 | 812 |
2019 | 689 |
2020 | 588 |
2021 | 512 |
Total | $ | 3,912 |

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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=35741047&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=35741047&loc=d3e13854-109267 + Details
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