Income Tax Provision	3 Months Ended
Income Tax Provision	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income Tax Provision	Income Tax Provision We had an effective income tax rate of 3.4% for the three months ended March 31, 2021, compared to negative 36.3% for the three months ended March 31, 2020. The higher effective tax rate for the three months ended March 31, 2021, as compared to the same period in 2020, was principally driven by a decrease in the 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% primarily due to excess tax benefits related to stock incentive awards and the tax benefit of research tax credits offset by state income taxes and non-deductible business expenses. The excess tax benefits related to stock incentive awards realized were $8.8 million for the three months ended March 31, 2021, compared to $22.1 million for the three months ended March 31, 2020. Excluding the excess tax benefits, the effective tax rate was 26.4% for the three months ended March 31, 2021, compared to 27% for the three months ended March 31, 2020. We made tax payments of $59,000 and $176,000 in the three months ended March 31, 2021, and 2020, respectively.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.