Income Taxes	9 Months Ended
Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 8—Income Taxes In determining the interim provision for income taxes, the Company uses the annual estimated effective tax rate applied to the actual year-to-date income and adds the tax effects of any discrete items in the reporting period in which they occur. For the nine months ended September 30, 2018, the Company’s effective tax rate differed from the United States (“U.S.”) federal statutory tax rate of 21% primarily due to state and foreign taxes, nondeductible stock-based compensation and the impact of tax benefits associated with stock-based awards. For the nine months ended September 30, 2017, the Company’s effective tax rate differed from the U.S. federal statutory tax rate of 35% primarily due to the impact of tax benefits associated with stock-based awards, nondeductible stock-based compensation and state and foreign taxes. For the three months ended September 30, 2018 and 2017, the provision for income taxes included $7.7 million and $3.2 million, respectively, of benefits associated with stock-based awards. For the nine months ended September 30, 2018 and 2017, the provision for income taxes included $14.2 million and $17.1 million, respectively, of benefits associated with stock-based awards. There were no material changes to the Company’s unrecognized tax benefits during the nine months ended September 30, 2018, and the Company does not expect to have any significant changes to unrecognized tax benefits within the next 12 months.

Note 8—Income Taxes

In determining the interim provision for income taxes, the Company uses the annual estimated effective tax rate applied to the actual year-to-date income and adds the tax effects of any discrete items in the reporting period in which they occur.

For the nine months ended September 30, 2018, the Company’s effective tax rate differed from the United States (“U.S.”) federal statutory tax rate of 21% primarily due to state and foreign taxes, nondeductible stock-based compensation and the impact of tax benefits associated with stock-based awards. For the nine months ended September 30, 2017, the Company’s effective tax rate differed from the U.S. federal statutory tax rate of 35% primarily due to the impact of tax benefits associated with stock-based awards, nondeductible stock-based compensation and state and foreign taxes.

For the three months ended September 30, 2018 and 2017, the provision for income taxes included $7.7 million and $3.2 million, respectively, of benefits associated with stock-based awards. For the nine months ended September 30, 2018 and 2017, the provision for income taxes included $14.2 million and $17.1 million, respectively, of benefits associated with stock-based awards.

There were no material changes to the Company’s unrecognized tax benefits during the nine months ended September 30, 2018, and the Company does not expect to have any significant changes to unrecognized tax benefits within the next 12 months.