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EMPLOYEE BENEFIT PLAN (Tables) | 6 Months Ended
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Jun. 30, 2019
EMPLOYEE BENEFIT PLAN |
Schedule of net periodic benefit cost and related components | ​
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​ | ​ | Three months ended | ​ | Six months ended
​ | ​ | June 30, | ​ | June 30,
(in thousands) |  | 2019 |  | 2018 |  | 2019 |  | 2018
Interest cost | ​ | $ | 490 | ​ | $ | 458 | ​ | $ | 980 | ​ | $ | 916
Expected return on plan assets | ​ |  | (650) | ​ |  | (709) | ​ |  | (1,300) | ​ |  | (1,418)
Amortization of net losses | ​ |  | 230 | ​ |  | 206 | ​ |  | 460 | ​ |  | 412
Net periodic benefit cost (credit) | ​ | $ | 70 | ​ | $ | (45) | ​ | $ | 140 | ​ | $ | (90)
Schedule of trading gains (losses) related to SERP assets | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three months ended | ​ | Six months ended
​ | ​ | June 30, | ​ | June 30,
(in thousands) |  | 2019 |  | 2018 |  | 2019 |  | 2018
Unrealized gains, net | ​ | $ | 785 | ​ | $ | 871 | ​ | $ | 3,636 | ​ | $ | 385

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- Definition Tabular disclosure of selected highly compensated employees to defer a portion of their compensation into the non-qualified Supplemental Retirement Plan ("SERP"). + References No definition available. + Details
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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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