Income Taxes	6 Months Ended
Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We consider new evidence (both positive and negative) at each reporting date that could affect our view of the future realization of deferred tax assets. Based upon the evaluation of all available evidence, and considering the projected U.S. pre-tax losses for 2018, we maintain a valuation allowance for our U.S. operations as of June 30, 2018. We maintained other valuation allowances for certain non-U.S. jurisdictions with cumulative losses. The effective income tax rates for the three and six months ended June 30, 2018 were 0.0% and (3.1)%, respectively, and (19.5%) and (19.8%) for the three and six months ended June 30, 2017, respectively, and were determined using an estimated annual effective tax rate after considering any discrete items for such periods. Due to the aforementioned valuation allowance against our U.S. deferred tax assets, the effective tax rate for the six months ended June 30, 2018 does not include the benefit of the current year U.S. tax losses. In the six months ended June 30, 2017, we recorded an overall tax expense due to the application of a full valuation allowance against the U.S. pre-tax losses coupled with a tax expense on foreign pre-tax earnings. The change in the effective tax rates relates primarily to the overall mix of income in our foreign jurisdictions. As disclosed in our 2017 10-K Note 21, our accounting for the Tax Cuts and Jobs Act (the "Tax Act") is incomplete; however, we were able to reasonably estimate certain effects, and consequently we recorded provisional adjustments associated with: (1) impact on deferred tax assets (DTAs) and deferred tax liabilities (DTLs) from reduction of U.S. federal corporate income tax rate; (2) the deemed repatriation transition tax; and (3) impact on valuation allowances. Additionally, as disclosed in our 2017 10-K Note 21, we were not yet able to reasonably estimate the effects of the Tax Act for the Global Intangible Low Income Tax (GILTI). There were no changes to these items during the second quarter of 2018, as we continue to evaluate the impacts of the Tax Act. Because of the complexity of the new GILTI tax rules, we are continuing to evaluate this provision of the Tax Act and the application of ASC 740. Under U.S. GAAP, we are allowed to make an accounting policy election of either (1) treating taxes due on future U.S. inclusions in taxable income related to GILTI as a current-period expense when incurred (the “period cost method”) or (2) factoring such amounts into our measurement of deferred taxes (the “deferred method”). Our selection of an accounting policy related to the new GILTI tax rules will depend, in part, on analyzing projections of our global overall mix of income to determine whether we expect to have future U.S. inclusions in taxable income related to GILTI and, if so, the expected impact. Because whether we expect to have future U.S. inclusions in taxable income related to GILTI depends on a number of different aspects of our estimated future global overall mix of income, we are not yet able to reasonably estimate the long-term effects of this provision of the Tax Act; therefore, we have not recorded any potential deferred tax effects related to GILTI in the consolidated financial statements and have not made a policy decision regarding whether to record deferred taxes on GILTI or to use the period cost method. We expect to complete our accounting within the prescribed measurement period.

Income Taxes

We consider new evidence (both positive and negative) at each reporting date that could affect our view of the future realization of deferred tax assets. Based upon the evaluation of all available evidence, and considering the projected U.S. pre-tax losses for 2018, we maintain a valuation allowance for our U.S. operations as of June 30, 2018. We maintained other valuation allowances for certain non-U.S. jurisdictions with cumulative losses.

The effective income tax rates for the three and six months ended June 30, 2018 were 0.0% and (3.1)%, respectively, and (19.5%) and (19.8%) for the three and six months ended June 30, 2017, respectively, and were determined using an estimated annual effective tax rate after considering any discrete items for such periods. Due to the aforementioned valuation allowance against our U.S. deferred tax assets, the effective tax rate for the six months ended June 30, 2018 does not include the benefit of the current year U.S. tax losses. In the six months ended June 30, 2017, we recorded an overall tax expense due to the application of a full valuation allowance against the U.S. pre-tax losses coupled with a tax expense on foreign pre-tax earnings. The change in the effective tax rates relates primarily to the overall mix of income in our foreign jurisdictions.

As disclosed in our 2017 10-K Note 21, our accounting for the Tax Cuts and Jobs Act (the "Tax Act") is incomplete; however, we were able to reasonably estimate certain effects, and consequently we recorded provisional adjustments associated with: (1) impact on deferred tax assets (DTAs) and deferred tax liabilities (DTLs) from reduction of U.S. federal corporate income tax rate; (2) the deemed repatriation transition tax; and (3) impact on valuation allowances. Additionally, as disclosed in our 2017 10-K Note 21, we were not yet able to reasonably estimate the effects of the Tax Act for the Global Intangible Low Income Tax (GILTI). There were no changes to these items during the second quarter of 2018, as we continue to evaluate the impacts of the Tax Act.

Because of the complexity of the new GILTI tax rules, we are continuing to evaluate this provision of the Tax Act and the application of ASC 740. Under U.S. GAAP, we are allowed to make an accounting policy election of either (1) treating taxes due on future U.S. inclusions in taxable income related to GILTI as a current-period expense when incurred (the “period cost method”) or (2) factoring such amounts into our measurement of deferred taxes (the “deferred method”). Our selection of an accounting policy related to the new GILTI tax rules will depend, in part, on analyzing projections of our global overall mix of income to determine whether we expect to have future U.S. inclusions in taxable income related to GILTI and, if so, the expected impact. Because whether we expect to have future U.S. inclusions in taxable income related to GILTI depends on a number of different aspects of our estimated future global overall mix of income, we are not yet able to reasonably estimate the long-term effects of this provision of the Tax Act; therefore, we have not recorded any potential deferred tax effects related to GILTI in the consolidated financial statements and have not made a policy decision regarding whether to record deferred taxes on GILTI or to use the period cost method. We expect to complete our accounting within the prescribed measurement period.