Income Taxes	3 Months Ended
Mar. 31, 2018
Income Taxes
Income Taxes	10. Income Taxes In December 2017, the President of the United States signed into law comprehensive tax reform legislation commonly known as Tax Cuts and Jobs Act (the “Tax Act”), which introduced significant changes to the previous tax law. This new legislation reduced the federal corporate income tax rate from 35% to 21% effective January 1, 2018. In December 2017, the Company recorded an increase to deferred tax expense of approximately $261.3 million on the date of enactment primarily relating to a reduction of our net deferred tax asset because of the rate change. The adjustments related to the application of the Tax Act continue to be provisional amounts to the extent that they are reasonably estimable and the Company will refine them as more information becomes available. The Company has not made any material measurement period adjustments related to these items in the three month period ended March 31, 2018. In accordance with Staff Accounting Bulletin No. 118, any adjustments to the provisional changes will be included in income tax expense or benefit in the appropriate period. The Company calculates the provision for income taxes during interim reporting periods by applying an estimate of the annual effective tax rate to the full year projected pretax book income or loss excluding certain discrete items. The effective tax rate (income taxes as a percentage of income from operations before income taxes) including discrete items was 25.67% for the three months ended March 31, 2018, as compared to 30.10% for the three months ended March 31, 2017, primarily due to the reduced federal income tax rate as a result of the Tax Act and higher earnings before income taxes.

10. Income Taxes

In December 2017, the President of the United States signed into law comprehensive tax reform legislation commonly known as Tax Cuts and Jobs Act (the “Tax Act”), which introduced significant changes to the previous tax law. This new legislation reduced the federal corporate income tax rate from 35% to 21% effective January 1, 2018. In December 2017, the Company recorded an increase to deferred tax expense of approximately $261.3 million on the date of enactment primarily relating to a reduction of our net deferred tax asset because of the rate change. The adjustments related to the application of the Tax Act continue to be provisional amounts to the extent that they are reasonably estimable and the Company will refine them as more information becomes available. The Company has not made any material measurement period adjustments related to these items in the three month period ended March 31, 2018. In accordance with Staff Accounting Bulletin No. 118, any adjustments to the provisional changes will be included in income tax expense or benefit in the appropriate period.

The Company calculates the provision for income taxes during interim reporting periods by applying an estimate of the annual effective tax rate to the full year projected pretax book income or loss excluding certain discrete items. The effective tax rate (income taxes as a percentage of income from operations before income taxes) including discrete items was 25.67% for the three months ended March 31, 2018, as compared to 30.10% for the three months ended March 31, 2017, primarily due to the reduced federal income tax rate as a result of the Tax Act and higher earnings before income taxes.