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v3.19.1

Goodwill | 3 Months Ended
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Mar. 31, 2019
Goodwill |
Goodwill | 5. Goodwill ​ The changes in the carrying amount of goodwill are as follows (in thousands): ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, | ​ | December 31, | ​
​ |  | 2019 |  | 2018 |
Balance at beginning of year | ​ | $ | 235,182 | ​ | $ | 200,584 | ​
Additions (See Note 4) | ​ |  | 678 | ​ |  | 34,598 | ​
Impairment adjustment | ​ | ​ | — | ​ | ​ | — | ​
Balance at end of period | ​ | $ | 235,860 | ​ | $ | 235,182 | ​
​

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- Definition The entire disclosure for goodwill and intangible assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -URI http://asc.fasb.org/topic&trid=2144416 + Details
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