v3.8.0.1

OTHER CURRENT ASSETS (Tables) | 12 Months Ended
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Dec. 31, 2017
Prepaid Expense and Other Assets, Current [Abstract] |
Other current assets [Table Text Block] | Other current assets consisted of the following:
| December 31,
| 2017 |  | 2016
| (Thousands of Dollars)
Axeon Term Loan | $ | — |  |  | $ | 110,000 |
Prepaid expenses | 15,982 |  |  | 14,894 |
Derivative assets | — |  |  | 155 |
Other | 6,526 |  |  | 7,637 |
Other current assets | $ | 22,508 |  |  | $ | 132,686 |

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