Income Taxes	3 Months Ended
Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	3. Income Taxes Our effective tax rates for the three months ended March 31, 2015 and 2014 were 36% and 40%, respectively. The decrease in the effective tax rate for the three months ended March 31, 2015 as compared to the same period in 2014 was primarily due to an increase in forecasted earnings in lower tax jurisdictions and a decrease in nondeductible losses and other discrete tax items relative to the amount of pre-tax income. The differences between our effective tax rates and the U.S. federal statutory income tax rate primarily result from our geographic mix of taxable income in various tax jurisdictions as well as the discrete tax items referenced above. We recognize liabilities when we believe that an uncertain tax position may not be fully sustained upon examination by the tax authorities. This requires significant judgment, the use of estimates, and the interpretation and application of complex tax laws. When facts and circumstances change, we reassess these probabilities and record any changes in the consolidated financial statements as appropriate. Our net unrecognized tax benefits, excluding interest and penalties, included in our consolidated balance sheets, were $56 million and $59 million as of March 31, 2015 and December 31, 2014, respectively.

Income Taxes

3 Months Ended

Mar. 31, 2015

3. Income Taxes

Our effective tax rates for the three months ended March 31, 2015 and 2014 were 36% and 40%, respectively. The decrease in the effective tax rate for the three months ended March 31, 2015 as compared to the same period in 2014 was primarily due to an increase in forecasted earnings in lower tax jurisdictions and a decrease in nondeductible losses and other discrete tax items relative to the amount of pre-tax income. The differences between our effective tax rates and the U.S. federal statutory income tax rate primarily result from our geographic mix of taxable income in various tax jurisdictions as well as the discrete tax items referenced above.

We recognize liabilities when we believe that an uncertain tax position may not be fully sustained upon examination by the tax authorities. This requires significant judgment, the use of estimates, and the interpretation and application of complex tax laws. When facts and circumstances change, we reassess these probabilities and record any changes in the consolidated financial statements as appropriate. Our net unrecognized tax benefits, excluding interest and penalties, included in our consolidated balance sheets, were $56 million and $59 million as of March 31, 2015 and December 31, 2014, respectively.