Income Taxes	9 Months Ended
Sep. 28, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We determine the tax provision for interim periods using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter we update our estimate of the annual effective tax rate, and if our estimated tax rate changes, we make a cumulative adjustment. Our effective tax rate was 18.9% and 20.7% for the first nine months of 2019 and 2018, respectively. The decrease in the effective tax rate in the first nine months of 2019 is primarily due to increased excess tax benefits recognized as a component of income tax expense due to elevated stock option exercise activity.

Income Taxes

9 Months Ended

Sep. 28, 2019

We determine the tax provision for interim periods using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter we update our estimate of the annual effective tax rate, and if our estimated tax rate changes, we make a cumulative adjustment. Our effective tax rate was 18.9% and 20.7% for the first nine months of 2019 and 2018, respectively. The decrease in the effective tax rate in the first nine months of 2019 is primarily due to increased excess tax benefits recognized as a component of income tax expense due to elevated stock option exercise activity.