Income Taxes	9 Months Ended
Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We provide for income taxes for each interim period based on the estimated annual effective tax rate for the year, adjusting for discrete items in the quarter in which they arise. The annual effective tax rate before discrete items was 40.4% and 38.1% for the nine months ended September 30, 2014 and 2013, respectively. The increase in the estimated annual effective tax rate for the nine months ended September 30, 2014 compared to the same period in 2013 was primarily due to the expiration of the federal research and development credit as of December 31, 2013. The 2014 annual effective tax rate differed from the statutory rate of 35.0% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the domestic production activities deduction. The 2013 annual effective tax rate differed from the statutory rate of 35.0% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the federal research and development credit claimed and the domestic production activities deduction.

Income Taxes

9 Months Ended

Sep. 30, 2014

We provide for income taxes for each interim period based on the estimated annual effective tax rate for the year, adjusting for discrete items in the quarter in which they arise. The annual effective tax rate before discrete items was 40.4% and 38.1% for the nine months ended September 30, 2014 and 2013, respectively. The increase in the estimated annual effective tax rate for the nine months ended September 30, 2014 compared to the same period in 2013 was primarily due to the expiration of the federal research and development credit as of December 31, 2013. The 2014 annual effective tax rate differed from the statutory rate of 35.0% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the domestic production activities deduction.

The 2013 annual effective tax rate differed from the statutory rate of 35.0% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the federal research and development credit claimed and the domestic production activities deduction.