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Major classes of assets and liabilities refining (Details 2) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Current assets: |  |
Total current assets held for sale | $ 430 | $ 479
Refining [Member] | Discontinued operations, held-for-sale or disposed by sale [Member] |  |
Current assets: |  |
Income taxes receivable | 0 | 1,778
Total current assets held for sale | 0 | 1,778
Total assets held for sale | 0 | 1,778
Deferred credits and other liabilities: |  |
Deferred income taxes | 0 | 37
Total noncurrent liabilities held for sale | 0 | 37
Total liabilities held for sale | $ 0 | $ 37

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