Income Taxes	9 Months Ended
Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We estimate our annual effective tax rate based on year-to-date operating results and our forecast for the remainder of the year, by jurisdiction, and apply this rate to the year-to-date operating results. If our actual results, by jurisdiction, differ from the forecasted operating results, our effective tax rate can change, affecting the tax expense for both successive interim results as well as the annual tax results. For the three and nine months ended September 30, 2015, we had a $65 million and $197 million tax benefit, respectively, on a loss before income taxes of $226 million and $948 million, respectively. Our results for the three months ended September 30, 2015, includes $49 million of restructuring charges, $44 million of project losses and $26 million of currency devaluation and related losses related to the Angolan kwanza and Kazakhstani tenge with no significant tax benefit. Our results for the nine months ended September 30, 2015, includes $159 million of restructuring charges, $112 million of litigation settlements, $71 million of project losses, $68 million of currency devaluation and related losses and $20 million of equity investment impairment, all with no significant tax benefit. We are continuously under tax examination in various jurisdictions. We cannot predict the timing or outcome regarding resolution of these tax examinations or if they will have a material impact on our financial statements. We continue to anticipate a possible reduction in the balance of uncertain tax positions of approximately $11 million in the next twelve months due to expiration of statutes of limitations, settlements and/or conclusions of tax examinations. For the three and nine months ended September 30, 2014, we had a tax provision of $98 million and $136 million on an income before income taxes of $187 million and $60 million, respectively. Our results for the three months ended September 30, 2014 were impacted by discrete income before tax items, including restructuring charges of approximately $154 million, with no significant tax benefit. Our results for the nine months ended September 30, 2014, included a $143 million impairment loss ($121 million, net of tax) to record the land drilling and workover rig operations in Russia and Venezuela at fair value and a $121 million impairment charge to goodwill triggered by the planned sale of our land drilling and workover rig operations in Russia and Venezuela, which was non-deductible for income tax purposes. Our results for the nine months ended September 30, 2014 were also impacted by discrete income before tax items, including restructuring charges of $283 million and project losses of $50 million, with no significant tax benefit.

Income Taxes

We estimate our annual effective tax rate based on year-to-date operating results and our forecast for the remainder of the year, by jurisdiction, and apply this rate to the year-to-date operating results. If our actual results, by jurisdiction, differ from the forecasted operating results, our effective tax rate can change, affecting the tax expense for both successive interim results as well as the annual tax results. For the three and nine months ended September 30, 2015, we had a $65 million and $197 million tax benefit, respectively, on a loss before income taxes of $226 million and $948 million, respectively. Our results for the three months ended September 30, 2015, includes $49 million of restructuring charges, $44 million of project losses and $26 million of currency devaluation and related losses related to the Angolan kwanza and Kazakhstani tenge with no significant tax benefit. Our results for the nine months ended September 30, 2015, includes $159 million of restructuring charges, $112 million of litigation settlements, $71 million of project losses, $68 million of currency devaluation and related losses and $20 million of equity investment impairment, all with no significant tax benefit.

We are continuously under tax examination in various jurisdictions. We cannot predict the timing or outcome regarding resolution of these tax examinations or if they will have a material impact on our financial statements. We continue to anticipate a possible reduction in the balance of uncertain tax positions of approximately $11 million in the next twelve months due to expiration of statutes of limitations, settlements and/or conclusions of tax examinations.

For the three and nine months ended September 30, 2014, we had a tax provision of $98 million and $136 million on an income before income taxes of $187 million and $60 million, respectively. Our results for the three months ended September 30, 2014 were impacted by discrete income before tax items, including restructuring charges of approximately $154 million, with no significant tax benefit. Our results for the nine months ended September 30, 2014, included a $143 million impairment loss ($121 million, net of tax) to record the land drilling and workover rig operations in Russia and Venezuela at fair value and a $121 million impairment charge to goodwill triggered by the planned sale of our land drilling and workover rig operations in Russia and Venezuela, which was non-deductible for income tax purposes. Our results for the nine months ended September 30, 2014 were also impacted by discrete income before tax items, including restructuring charges of $283 million and project losses of $50 million, with no significant tax benefit.