v3.8.0.1

ACCRUED LIABILITIES | 12 Months Ended
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Dec. 31, 2017
Accrued Liabilities, Current [Abstract] |
ACCRUED LIABILITIES | ACCRUED LIABILITIES Accrued liabilities consisted of the following:
| December 31,
| 2017 |  | 2016
| (Thousands of Dollars)
Employee wages and benefit costs | $ | 16,963 |  |  | $ | 30,807 |
Unearned income | 18,243 |  |  | 14,355 |
Other | 26,372 |  |  | 15,323 |
Accrued liabilities | $ | 61,578 |  |  | $ | 60,485 |

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