Income Taxes	9 Months Ended
Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Our income tax provision was $19.3 million and $75.0 million in the three and nine months ended September 30, 2018, respectively, compared to $1.2 million and $65.9 million for the same periods in 2017. The effective tax rates were 11.4% and 20.6% in the three and nine months ended September 30, 2018, respectively, compared to 1.9% and 20.5% for the same periods in 2017. The increase in the effective tax rate for the three months ended September 30, 2018 compared to the same period in 2017 was primarily due to the release of a valuation allowance held against certain foreign net operating losses in 2017 and the impacts of movements on unrecognized tax benefits, partially offset by a decrease in the U.S. corporate income tax rate. The effective tax rate for the nine months ended September 30, 2018 was in line with the same period in 2017. The effective tax rate for the three months ended September 30, 2018 was lower than the Irish statutory rate of 12.5% primarily due to the release of reserves related to unrecognized tax benefits upon the expiration of a statute of limitations. The effective tax rate for the nine months ended September 30, 2018 was higher than the Irish statutory rate of 12.5% primarily due to income taxable at a rate higher than the Irish statutory rate, various expenses not deductible for income tax purposes and unrecognized tax benefits. We do not provide for Irish income taxes on undistributed earnings of our foreign operations that are intended to be indefinitely reinvested in our foreign subsidiaries. Our net deferred tax liability primarily arose due to the acquisition of Celator. The balance is net of deferred tax assets which are comprised primarily of U.S. federal and state tax credits, U.S. federal and state and foreign net operating loss carryforwards and other temporary differences. We maintain a valuation allowance against certain foreign and U.S. federal and state deferred tax assets. Each reporting period, we evaluate the need for a valuation allowance on our deferred tax assets by jurisdiction and adjust our estimates as more information becomes available. We are required to recognize the financial statement effects of a tax position when it is more likely than not, based on the technical merits, that the position will be sustained upon examination. As a result, we have recorded an unrecognized tax benefit for certain tax benefits which we judge may not be sustained upon examination. Our most significant tax jurisdictions are Ireland, the U.S. (both at the federal level and in various state jurisdictions), Italy and France. These jurisdictions have statutes of limitations ranging from three to five years. However, in the U.S. (at the federal level and in most states), carryforward tax attributes that were generated in 2013 and earlier may still be adjusted upon examination by the tax authorities. Certain of our subsidiaries are currently under examination by the French tax authorities for the years ended December 31, 2012, 2013, 2015, 2016 and 2017. These examinations may lead to ordinary course adjustments or proposed adjustments to our taxes. In December 2015, we received proposed tax assessment notices, and, in October 2018, we received revised tax assessment notices from the French tax authorities for 2012 and 2013 relating to certain transfer pricing adjustments. The notices provide for additional French tax of approximately $43 million, including interest and penalties through the date of the proposed assessment, translated at the foreign exchange rate at September 30, 2018. We disagree with the assessments and are contesting them vigorously. During the three and nine months ended September 30, 2018, we recorded an income tax expense of $2.9 million as a provisional measurement period adjustment to the provisional estimates recorded as of December 31, 2017 in accordance with the SEC’s Staff Accounting Bulletin No. 118, or SAB 118. The provisional measurement period adjustment was due to additional analysis on the one-time transition tax on deemed repatriated earnings of foreign subsidiaries. We will continue to analyze the impact of the U.S. Tax Cuts and Jobs Act of 2017 under SAB 118 and may record further adjustments to provisional amounts as our analyses are completed in the fourth quarter of 2018.

Income Taxes

Our income tax provision was $19.3 million and $75.0 million in the three and nine months ended September 30, 2018, respectively, compared to $1.2 million and $65.9 million for the same periods in 2017. The effective tax rates were 11.4% and 20.6% in the three and nine months ended September 30, 2018, respectively, compared to 1.9% and 20.5% for the same periods in 2017. The increase in the effective tax rate for the three months ended September 30, 2018 compared to the same period in 2017 was primarily due to the release of a valuation allowance held against certain foreign net operating losses in 2017 and the impacts of movements on unrecognized tax benefits, partially offset by a decrease in the U.S. corporate income tax rate. The effective tax rate for the nine months ended September 30, 2018 was in line with the same period in 2017. The effective tax rate for the three months ended September 30, 2018 was lower than the Irish statutory rate of 12.5% primarily due to the release of reserves related to unrecognized tax benefits upon the expiration of a statute of limitations. The effective tax rate for the nine months ended September 30, 2018 was higher than the Irish statutory rate of 12.5% primarily due to income taxable at a rate higher than the Irish statutory rate, various expenses not deductible for income tax purposes and unrecognized tax benefits. We do not provide for Irish income taxes on undistributed earnings of our foreign operations that are intended to be indefinitely reinvested in our foreign subsidiaries.

Our net deferred tax liability primarily arose due to the acquisition of Celator. The balance is net of deferred tax assets which are comprised primarily of U.S. federal and state tax credits, U.S. federal and state and foreign net operating loss carryforwards and other temporary differences. We maintain a valuation allowance against certain foreign and U.S. federal and state deferred tax assets. Each reporting period, we evaluate the need for a valuation allowance on our deferred tax assets by jurisdiction and adjust our estimates as more information becomes available.

We are required to recognize the financial statement effects of a tax position when it is more likely than not, based on the technical merits, that the position will be sustained upon examination. As a result, we have recorded an unrecognized tax benefit for certain tax benefits which we judge may not be sustained upon examination. Our most significant tax jurisdictions are Ireland, the U.S. (both at the federal level and in various state jurisdictions), Italy and France. These jurisdictions have statutes of limitations ranging from three to five years. However, in the U.S. (at the federal level and in most states), carryforward tax attributes that were generated in 2013 and earlier may still be adjusted upon examination by the tax authorities. Certain of our subsidiaries are currently under examination by the French tax authorities for the years ended December 31, 2012, 2013, 2015, 2016 and 2017. These examinations may lead to ordinary course adjustments or proposed adjustments to our taxes. In December 2015, we received proposed tax assessment notices, and, in October 2018, we received revised tax assessment notices from the French tax authorities for 2012 and 2013 relating to certain transfer pricing adjustments. The notices provide for additional French tax of approximately $43 million, including interest and penalties through the date of the proposed assessment, translated at the foreign exchange rate at September 30, 2018. We disagree with the assessments and are contesting them vigorously.

During the three and nine months ended September 30, 2018, we recorded an income tax expense of $2.9 million as a provisional measurement period adjustment to the provisional estimates recorded as of December 31, 2017 in accordance with the SEC’s Staff Accounting Bulletin No. 118, or SAB 118. The provisional measurement period adjustment was due to additional analysis on the one-time transition tax on deemed repatriated earnings of foreign subsidiaries. We will continue to analyze the impact of the U.S. Tax Cuts and Jobs Act of 2017 under SAB 118 and may record further adjustments to provisional amounts as our analyses are completed in the fourth quarter of 2018.