Income Taxes	6 Months Ended
Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes We operate on a global basis and are subject to numerous and complex tax laws and regulations. Additionally, tax laws continue to undergo rapid changes in both application and interpretation by various countries, including state aid interpretations and the Organization for Economic Cooperation and Development led initiatives. Our income tax filings are subject to examinations by taxing authorities throughout the world. Income tax audits may require an extended period of time to reach resolution and may result in significant income tax adjustments when interpretation of tax laws or allocation of company profits is disputed. Although ultimate timing is uncertain, the net amount of tax liability for unrecognized tax benefits may change within the next twelve months due to changes in audit status, expiration of statutes of limitations, settlements of tax assessments and other events. Management’s best estimate of such change is within the range of a $300 million decrease to a $50 million increase. Our U.S. Federal income tax returns have been audited through 2009 and are currently under audit for years 2010-2014. The IRS has proposed adjustments for years 2005-2009, reallocating profits between certain of our U.S. and foreign subsidiaries. We have disputed these adjustments and intend to continue to vigorously defend our positions. For years 2005-2007, we have filed a petition with the U.S. Tax Court. For years 2008-2009, we are pursuing resolution through the IRS Administrative Appeals Process. Our effective tax rate (“ETR”) has been affected by the significant expenses associated with the Biomet merger and other acquisitions which have generally been recognized in higher income tax jurisdictions. Accordingly, this has reduced our ETR as our earnings have been lower in these higher income tax jurisdictions. In the six month period ended June 30, 2017, we recognized a tax benefit of $69.7 million resulting from a tax restructuring that lowered the tax rate on certain deferred tax liabilities recorded on intangible assets recognized in the Biomet merger acquisition-related accounting. In the three and six month periods ended June 30, 2017, we recognized tax benefits of $67.0 million and $88.8 million, respectively, related to resolution of certain tax matters. In the three and six month periods ended June 30, 2017, we recognized net income tax expense of $10.5 million that related to previous periods for certain tax restructurings and product liability matters. We have evaluated the effect of these out-of-period adjustments on the three and six month periods ended June 30, 2017, as well as on the previous interim and annual periods in which they should have been recognized, and concluded for both quantitative and qualitative reasons that these adjustments are not material to any of the periods affected. Further, we do not believe these adjustments will be material to our estimated net earnings for the full year ended December 31, 2017.

11. Income Taxes

We operate on a global basis and are subject to numerous and complex tax laws and regulations. Additionally, tax laws continue to undergo rapid changes in both application and interpretation by various countries, including state aid interpretations and the Organization for Economic Cooperation and Development led initiatives. Our income tax filings are subject to examinations by taxing authorities throughout the world. Income tax audits may require an extended period of time to reach resolution and may result in significant income tax adjustments when interpretation of tax laws or allocation of company profits is disputed. Although ultimate timing is uncertain, the net amount of tax liability for unrecognized tax benefits may change within the next twelve months due to changes in audit status, expiration of statutes of limitations, settlements of tax assessments and other events. Management’s best estimate of such change is within the range of a $300 million decrease to a $50 million increase.

Our U.S. Federal income tax returns have been audited through 2009 and are currently under audit for years 2010-2014. The IRS has proposed adjustments for years 2005-2009, reallocating profits between certain of our U.S. and foreign subsidiaries. We have disputed these adjustments and intend to continue to vigorously defend our positions. For years 2005-2007, we have filed a petition with the U.S. Tax Court. For years 2008-2009, we are pursuing resolution through the IRS Administrative Appeals Process.

Our effective tax rate (“ETR”) has been affected by the significant expenses associated with the Biomet merger and other acquisitions which have generally been recognized in higher income tax jurisdictions. Accordingly, this has reduced our ETR as our earnings have been lower in these higher income tax jurisdictions. In the six month period ended June 30, 2017, we recognized a tax benefit of $69.7 million resulting from a tax restructuring that lowered the tax rate on certain deferred tax liabilities recorded on intangible assets recognized in the Biomet merger acquisition-related accounting. In the three and six month periods ended June 30, 2017, we recognized tax benefits of $67.0 million and $88.8 million, respectively, related to resolution of certain tax matters. In the three and six month periods ended June 30, 2017, we recognized net income tax expense of $10.5 million that related to previous periods for certain tax restructurings and product liability matters. We have evaluated the effect of these out-of-period adjustments on the three and six month periods ended June 30, 2017, as well as on the previous interim and annual periods in which they should have been recognized, and concluded for both quantitative and qualitative reasons that these adjustments are not material to any of the periods affected. Further, we do not believe these adjustments will be material to our estimated net earnings for the full year ended December 31, 2017.