Income Taxes	3 Months Ended
Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Our effective income tax rate was 12.8% for the three months ended March 31, 2018 and 26.4% in the comparable period in 2017. The 2018 tax rate reflects the enactment of the Tax Cuts and Jobs Act of 2017 (TCJA), which permanently reduced the U.S. corporate statutory rate from 35% to 21% effective January 1, 2018. The 2018 tax rate reflects tax benefits for sales of U.S. manufactured goods to non-U.S. customers and research and development credits as well as a 4% benefit from discrete tax benefits, primarily related to share-based payments recorded in the first quarter of 2018. The 2017 tax rate of 26.4% reflects the 35% statutory tax rate reduced by tax benefits for research and development credits, U.S. manufacturing activity and share-based payments. In 2017, in accordance with U.S. Securities and Exchange Commission Staff Accounting Bulletin No. 118, we recorded provisional amounts related to the TCJA, including the remeasurement of our U.S. net deferred tax liabilities and ancillary state tax effects, as well as the repatriation tax. We continue to assess available tax methods and elections, refine our computation of the repatriation tax and evaluate regulatory guidance, which may result in changes to our tax estimates. Federal income tax audits have been settled for all years prior to 2013. The Internal Revenue Service (IRS) is currently examining the 2013-2014 tax years. We are also subject to examination in major state and international jurisdictions for the 2001-2016 tax years. We believe appropriate provisions for all outstanding tax issues have been made for all jurisdictions and all open years. Audit outcomes and the timing of audit settlements are subject to significant uncertainty. It is reasonably possible that within the next 12 months unrecognized tax benefits related to federal and state matters under audit may decrease by up to $540 and $435, respectively, based on current estimates.

Income Taxes

Our effective income tax rate was 12.8% for the three months ended March 31, 2018 and 26.4% in the comparable period in 2017. The 2018 tax rate reflects the enactment of the Tax Cuts and Jobs Act of 2017 (TCJA), which permanently reduced the U.S. corporate statutory rate from 35% to 21% effective January 1, 2018. The 2018 tax rate reflects tax benefits for sales of U.S. manufactured goods to non-U.S. customers and research and development credits as well as a 4% benefit from discrete tax benefits, primarily related to share-based payments recorded in the first quarter of 2018. The 2017 tax rate of 26.4% reflects the 35% statutory tax rate reduced by tax benefits for research and development credits, U.S. manufacturing activity and share-based payments.

In 2017, in accordance with U.S. Securities and Exchange Commission Staff Accounting Bulletin No. 118, we recorded provisional amounts related to the TCJA, including the remeasurement of our U.S. net deferred tax liabilities and ancillary state tax effects, as well as the repatriation tax. We continue to assess available tax methods and elections, refine our computation of the repatriation tax and evaluate regulatory guidance, which may result in changes to our tax estimates.

Federal income tax audits have been settled for all years prior to 2013. The Internal Revenue Service (IRS) is currently examining the 2013-2014 tax years. We are also subject to examination in major state and international jurisdictions for the 2001-2016 tax years. We believe appropriate provisions for all outstanding tax issues have been made for all jurisdictions and all open years.

Audit outcomes and the timing of audit settlements are subject to significant uncertainty. It is reasonably possible that within the next 12 months unrecognized tax benefits related to federal and state matters under audit may decrease by up to $540 and $435, respectively, based on current estimates.