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MARKETABLE SECURITIES (Tables) | 6 Months Ended
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Jun. 30, 2019
MARKETABLE SECURITIES |
Schedule of net realized (losses) gains and reclassification of net realized (losses) gains from other comprehensive income | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three months ended | ​ | Six months ended
​ | ​ | June 30, | ​ | June 30,
(in thousands) |  | 2019 |  | 2018 |  | 2019 |  | 2018
Net realized gain (loss) | ​ | $ | 0 | ​ | $ | (1) | ​ | $ | 4 | ​ | $ | (20)
Reclassification of net realized gains from other comprehensive income | ​ | $ | 0 | ​ | $ | (1) | ​ | $ | 4 | ​ | $ | (20)
Schedule of gross unrealized gains (losses) on marketable securities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | June 30, 2019 | ​ | December 31, 2018
​ | ​ | Gross unrealized | ​ | Gross unrealized
(in thousands) |  | Gains |  | (Losses) |  | Gains |  | (Losses)
Municipal Obligations | ​ | $ | — | ​ | $ | — | ​ | $ | 2 | ​ | $ | (2)
Corporate Obligations | ​ |  | — | ​ |  | — | ​ |  | 1 | ​ |  | (10)
​ | ​ | $ | — | ​ | $ | — | ​ | $ | 3 | ​ | $ | (12)
Schedule of amortized cost basis, fair value and net unrealized gains on the available-for-sale securities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, 2018
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Net
​ | ​ | Amortized | ​ | Fair | ​ | Unrealized
Type of Securities |  | Cost Basis |  | Value |  | Losses
(in thousands) |  | ​ |  |  | ​ |  |  | ​ |
Municipal Obligations | ​ | $ | 1,490 | ​ | $ | 1,490 | ​ | $ | —
Corporate Obligations | ​ |  | 6,184 | ​ |  | 6,175 | ​ |  | (9)
Total | ​ | $ | 7,674 | ​ | $ | 7,665 | ​ | $ | (9)
​

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- Definition Tabular disclosure of net realized gains and the reclassification of net realized gains from other comprehensive income. + References No definition available. + Details
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- Definition Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities. + References No definition available. + Details
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- Definition Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -URI http://asc.fasb.org/topic&trid=2196928 + Details
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