|6 Months Ended
Jun. 30, 2015
|Income Tax Disclosure [Abstract]
Our consolidated effective tax rate increased to 34.5% in the second quarter of 2015 compared with 33.5% in the same period of 2014, primarily due to the $1.066 billion pre-tax charge in the prior year associated with certain health and welfare benefit plan changes, which generated a tax benefit at a rate higher than the consolidated effective tax rate. This was partially offset by favorable changes in the proportion of our taxable income in certain U.S. and non-U.S. jurisdictions and an increase in U.S. Federal and state tax credits realized in comparison to amounts previously estimated.
On a year-to-date basis, our consolidated effective tax rate decreased to 34.9% in 2015 from 35.2% in 2014, due to favorable changes in the proportion of our taxable income in certain U.S. and non-U.S. jurisdictions and an increase in U.S. Federal and state tax credits realized in comparison to amounts previously estimated.
In July 2013, we began resolution discussions with IRS Appeals on several income tax matters. In the second quarter of 2014, we reached a final resolution with IRS Appeals on all income tax matters for the 2005 through 2007 tax years and received a net refund of tax and interest totaling $145 million during the second quarter of 2014. The resolution of these matters and subsequent refund of tax and interest did not have a material impact on net income.
As discussed in our Annual Report on Form 10-K for the year ended December 31, 2014, we have recognized liabilities for uncertain tax positions. We reevaluate these uncertain tax positions on a quarterly basis. A number of years may elapse before an uncertain tax position is audited and ultimately settled. It is difficult to predict the ultimate outcome or the timing of resolution for uncertain tax positions. It is reasonably possible that the amount of unrecognized tax benefits could significantly increase or decrease within the next twelve months. Items that may cause changes to unrecognized tax benefits include the timing of interest deductions and the allocation of income and expense between tax jurisdictions. These changes could result from the settlement of ongoing litigation, the completion of ongoing examinations, the expiration of the statute of limitations or other unforeseen circumstances. At this time, an estimate of the range of the reasonably possible change cannot be made.