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Reconciliation of income and expenses (Details 9) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Income (loss) from discontinued operations, net of tax | [1] |  |  |  |  |  |  |  |  | $ (300,354) | $ (834,080) | $ 109,311
Loss from discontinued operations attributable to noncontrolling interest |  |  |  |  |  |  |  |  |  | (131,691) | (35,256) | (3,895)
Income (loss) from discontinued operations attributable to the Company |  | $ (816) | $ (5,400) | $ (155,451) | $ (6,996) | $ (3,368) | $ (213,334) | $ (255,665) | $ (326,457) |  |  |
Discontinued operations, held-for-sale or disposed by sale [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Operating revenues |  |  |  |  |  |  |  |  |  | 123,024 | 363,115 | 547,571
Operating expenses |  |  |  |  |  |  |  |  |  | 513,813 | 1,666,941 | 386,651
Operating income (loss) |  |  |  |  |  |  |  |  |  | (390,789) | (1,303,826) | 160,920
Other income |  |  |  |  |  |  |  |  |  | 306 | 3,149 | 1,898
Interest expense |  |  |  |  |  |  |  |  |  | 1,753 | 2,124 | 145
Income (loss) from discontinued operations before income taxes |  |  |  |  |  |  |  |  |  | (392,236) | (1,302,801) | 162,673
Income taxes |  |  |  |  |  |  |  |  |  | (91,882) | (468,721) | 53,362
Income (loss) from discontinued operations, net of tax |  |  |  |  |  |  |  |  |  | (300,354) | (834,080) | 109,311
Loss from discontinued operations attributable to noncontrolling interest |  |  |  |  |  |  |  |  |  | (131,691) | (35,256) | (3,895)
Income (loss) from discontinued operations attributable to the Company |  |  |  |  |  |  |  |  |  | (168,663) | (798,824) | 113,206
Refining [Member] | Discontinued operations, held-for-sale or disposed by sale [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Pretax loss attributable to the company |  |  |  |  |  |  |  |  |  | $ (253,500) | $ (31,500) | $ (3,200)
[1] | Includes eliminations for the presentation of income tax adjustments between continuing and discontinued operations.

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