Income Tax Provision

6 Months Ended

Jun. 30, 2019

Income Tax Disclosure [Abstract]

Income Tax Provision

Income Tax Provision

We had an effective income tax rate of 12.1% and 17.0% for the three and six months ended June 30, 2019, respectively, compared to negative 3.9% and 0.2% for the three and six months ended June 30, 2018, respectively. The increase in the effective tax rate for the three and six months ended June 30, 2019, as compared to the same period in 2018 was principally due to the decrease in excess tax benefits related to stock incentive awards.

The effective income tax rates for the periods presented were different from the statutory United States federal income tax rate of 21% due to excess tax benefits related to stock incentive awards, state income taxes, non-deductible business expenses, and the tax benefit of research tax credits. The excess tax benefits related to stock incentive awards realized was $5.4 million and $7.0 million for the three and six months ended June 30, 2019, respectively, compared to $11.5 million and $20.7 million for the three and six months ended June 30, 2018, respectively. Excluding the excess tax benefits, the effective rate was 26.9% and 26.8% for the three and six months ended June 30, 2019, compared to 26.7% and 27.0% for the three and six months ended June 30, 2018, respectively.

We made tax payments of $14.8 million and $7.1 million in the six months ended June 30, 2019, and 2018, respectively.