Income Taxes (Policy)	12 Months Ended
Income Taxes (Policy)	Dec. 31, 2017
Income Taxes [Abstract]
Income Taxes	The Tax Cuts and Jobs Act (the “Tax Act”) was enacted on December 22, 2017, and includes significant changes to the U.S. corporate tax system. Effective January 1, 2018, the Tax Act reduced the U.S. federal corporate tax rate from 35 percent to 21 percent, and transitioned the U.S. federal tax system from a worldwide tax system to a territorial tax system, and eliminated or reduced certain domestic deductions among other changes. In converting to the new territorial tax system, a deemed repatriation tax on previously tax-deferred earnings of certain foreign subsidiaries was required to be recognized as of December 31, 2017, and will be payable over eight years. On December 22, 2017, the SEC issued Staff Accounting Bulletin 118 (“SAB 118”) that provides additional guidance allowing companies to apply a measurement period of up to twelve months to account for the impacts of the Tax Act in their financial statements. As of December 31, 2017, we have accounted for the impacts of the Tax Act to the extent a reasonable estimate could be made and we recognized provisional amounts related to the deemed repatriation tax, offset by the remeasurement of our deferred tax assets and liabilities, and other adjustments. The provisional amounts are included as a component of income tax expense from continuing operations as a reasonable estimate of the effects of the Tax Act on our U.S. federal and state tax obligations. We will continue to refine our estimates throughout the measurement period or until the accounting is complete as allowed under SAB 118. As a result of the Tax Act we are no longer asserting indefinite reversal under ASC 740-30-25 for undistributed earnings of non-U.S. subsidiaries as of December 31, 2017. We have recorded a provisional amount of $48.8 million for the deemed repatriation tax liability related to these earnings. The provision for income taxes is determined using the asset and liability approach of accounting for income taxes. Under this approach, deferred taxes represent the estimated future tax effects of temporary differences between book and tax treatment of assets and liabilities and carryforwards to the extent they are realizable. We record a valuation allowance to reduce our deferred tax assets to the amount that is more likely than not to be realized. While we consider future taxable income and ongoing prudent and feasible tax planning strategies in assessing the need for a valuation allowance, in the event we determine that we would be able to realize our deferred tax assets in the future in excess of the net recorded amount, a reduction of the valuation allowance would increase income in the period such determination was made. Likewise, should we determine that we would not be able to realize all or part of our net deferred tax asset in the future, a reduction to the deferred tax asset would be charged to income in the period such determination was made.

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.