v3.8.0.1

HEALTH, SAFETY AND ENVIRONMENTAL MATTERS (Tables) | 12 Months Ended
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Dec. 31, 2017
Environmental Remediation Obligations [Abstract] |
Schedule of Environmental Accrual Rollforward [Table Text Block] | The balance of and changes in the accruals for environmental matters were as follows:
| Year Ended December 31,
| 2017 |  | 2016
| (Thousands of Dollars)
Balance as of the beginning of year | $ | 5,120 |  |  | $ | 7,667 |
Additions to accrual | 3,186 |  |  | 870 |
Payments | (2,675 | ) |  | (3,302 | )
Foreign currency translation | 52 |  |  | (115 | )
Balance as of the end of year | $ | 5,683 |  |  | $ | 5,120 |
Environmental Accruals By Balance Sheet Location [Table Text Block] | Accruals for environmental matters are included in the consolidated balance sheets as follows:
| December 31,
| 2017 |  | 2016
| (Thousands of Dollars)
Accrued liabilities | $ | 3,054 |  |  | $ | 3,281 |
Other long-term liabilities | 2,629 |  |  | 1,839 |
Accruals for environmental matters | $ | 5,683 |  |  | $ | 5,120 |

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