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Major classes of assets and liabilities Refining (Details 2) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017
--- | --- | --- | ---
Current assets: |  |  |  |  |  |
Total current assets held for sale |  | $ 458 |  | $ 479 |  | $ 7,290
Current liabilities: |  |  |  |  |  |
Total current liabilities held for sale |  | 11,726 |  | 11,993 |  | 2,394
Refining | Discontinued operations, held-for-sale or disposed of by sale |  |  |  |  |  |
Current assets: |  |  |  |  |  |
Income taxes receivable |  | 1,858 | [1] | 1,778 | [1] | 11,756
Total current assets held for sale |  | 1,858 |  | 1,778 |  | 11,756
Total assets held for sale |  | 1,858 |  | 1,778 |  | 11,756
Current liabilities: |  |  |  |  |  |
Accounts payable |  | 0 |  | 0 |  | 16
Total current liabilities held for sale |  | 0 |  | 0 |  | 16
Noncurrent liabilities: |  |  |  |  |  |
Deferred income taxes (b) | [2] | 37 |  | 37 |  | 55
Total noncurrent liabilities held for sale |  | 37 |  | 37 |  | 55
Total liabilities held for sale |  | $ 37 |  | $ 37 |  | $ 71
[1] | On the Company's Consolidated Balance Sheets, these amounts were reclassified to taxes payable and are reflected in current liabilities held for sale.
[2] | On the Company's Consolidated Balance Sheets, these amounts were reclassified to deferred charges and other assets - deferred income taxes and are reflected in noncurrent assets held for sale.

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