Income Taxes	3 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense for the three months ended March 31, 2019 was $105.1 million, representing an effective tax rate of 23.2%. The prior-year three-month provision for income taxes was $102.1 million, representing an effective tax rate of 21.1%, and included a $22.6 million benefit resulting from a change in accounting method regarding the timing of tax deductions for software development-related expenses, partially offset by a $15.8 million net provision recorded in the prior-year three-month period representing adjustments to the initial estimated impact of the Tax Cuts and Jobs Act enacted in the fourth quarter of 2017.

Income Taxes

3 Months Ended

Mar. 31, 2019

Income tax expense for the three months ended March 31, 2019 was $105.1 million, representing an effective tax rate of 23.2%.

The prior-year three-month provision for income taxes was $102.1 million, representing an effective tax rate of 21.1%, and included a $22.6 million benefit resulting from a change in accounting method regarding the timing of tax deductions for software development-related expenses, partially offset by a $15.8 million net provision recorded in the prior-year three-month period representing adjustments to the initial estimated impact of the Tax Cuts and Jobs Act enacted in the fourth quarter of 2017.