Income Taxes	3 Months Ended
Mar. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s effective income tax rate, including discrete items, was 39.2% and 30.4% for the three months ended March 31, 2014 and 2013, respectively. The effective income tax rate is based upon estimated income for the year, the estimated composition of the income in different jurisdictions and discrete adjustments, if any, in the applicable quarterly periods, including retroactive changes in tax legislation, settlements of tax audits or assessments, the resolution or identification of tax position uncertainties and acquisitions of other companies. The discrete items in the first quarter of 2014 include a deferred tax charge, the tax effect of certain stock options and interest and penalties related to uncertain tax positions. For the three months ended March 31, 2014, the effective income tax rate was higher than the federal statutory tax rate mainly due to the effects of accounting for stock-based compensation in accordance with the authoritative guidance for share-based payments and state income tax. For the three months ended March 31, 2013, the effective income tax rate was lower than the federal statutory tax rate mainly due to the composition of income in foreign jurisdictions that is taxed at lower rates compared to the statutory tax rates in the United States, as well as the reinstatement of the federal research and development credit at the beginning of 2013 which was retroactive to 2012.

Income Taxes

3 Months Ended

Mar. 31, 2014

The Company’s effective income tax rate, including discrete items, was 39.2% and 30.4% for the three months ended March 31, 2014 and 2013, respectively. The effective income tax rate is based upon estimated income for the year, the estimated composition of the income in different jurisdictions and discrete adjustments, if any, in the applicable quarterly periods, including retroactive changes in tax legislation, settlements of tax audits or assessments, the resolution or identification of tax position uncertainties and acquisitions of other companies. The discrete items in the first quarter of 2014 include a deferred tax charge, the tax effect of certain stock options and interest and penalties related to uncertain tax positions.

For the three months ended March 31, 2014, the effective income tax rate was higher than the federal statutory tax rate mainly due to the effects of accounting for stock-based compensation in accordance with the authoritative guidance for share-based payments and state income tax. For the three months ended March 31, 2013, the effective income tax rate was lower than the federal statutory tax rate mainly due to the composition of income in foreign jurisdictions that is taxed at lower rates compared to the statutory tax rates in the United States, as well as the reinstatement of the federal research and development credit at the beginning of 2013 which was retroactive to 2012.