Income Tax Provision

9 Months Ended

Sep. 30, 2017

Income Tax Disclosure [Abstract]

Income Tax Provision

Income Tax Provision

For the three and nine months ended September 30, 2017, we had effective income tax rates of 12.1% and 12.3%, respectively, compared to 2.7% and 16.5% for the three and nine months ended September 30, 2016, respectively. The effective income tax rates for the periods presented were different from the statutory United States federal income tax rate of 35% principally due to excess tax benefits related to stock option exercises. The excess tax benefits related to stock option exercises realized were $9.0 million and $27.6 million for the three and nine months ended September 30, 2017, respectively, compared to $13.3 million and $20.8 million for the three and nine months ended September 30, 2016, respectively. The change in the effective income tax rates for the three and nine months ended September 30, 2017 as compared to the prior year periods is mainly due to the change in excess tax benefits related to stock option exercises realized. Excluding the excess tax benefits, the effective rates were 32.8% and 36.0% for the three and nine months ended September 30, 2017, respectively, compared to 39.3% and 38.5% for the three and nine months ended September 30, 2016, respectively. Other differences from our federal statutory income tax rate included state income taxes, non-deductible business expenses, tax credits, and the tax benefit of the domestic production activities deduction.

We made tax payments of $29.0 million and $25.0 million in the nine months ended September 30, 2017, and September 30, 2016, respectively.