Income Taxes	3 Months Ended
Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes. On December 22, 2017, the United States enacted tax reform legislation commonly known as the Tax Cuts and Jobs Act (the “Tax Act”), resulting in significant modifications to U.S. tax law. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118 (“SAB 118”), which provides guidance on accounting for the tax effects of the Tax Act. SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under ASC 740. As of March 31, 2018, we have not made a measurement period adjustment and the accounting for the Tax Act remains incomplete. Income tax expense for the quarter ended March 31, 2018 was $1,255, for an effective tax rate for the quarter of 12.3 percent. The effective tax rate differs from the 21 percent federal statutory rate (as lowered by the Tax Act) on pretax income primarily due to ASU 2016-09, Compensation - Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting and state taxes, including state income tax credits in Indiana and Kansas. Income tax expense for the quarter ended March 31, 2017 was $2,854, for an effective tax rate of 24.7 percent for the quarter. The effective tax rate differed from the 35 percent federal statutory rate on pretax income, primarily due to the impact of income tax benefits related to share-based compensation as accounted for in ASU 2016-09, Compensation - Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting, which was adopted by the Company during the quarter ended September 30, 2016, the domestic production activities deduction, and state taxes, including state income tax credits in Indiana and Kansas.

Income Taxes.

On December 22, 2017, the United States enacted tax reform legislation commonly known as the Tax Cuts and Jobs Act (the “Tax Act”), resulting in significant modifications to U.S. tax law. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118 (“SAB 118”), which provides guidance on accounting for the tax effects of the Tax Act. SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under ASC 740. As of March 31, 2018, we have not made a measurement period adjustment and the accounting for the Tax Act remains incomplete.

Income tax expense for the quarter ended March 31, 2018 was $1,255, for an effective tax rate for the quarter of 12.3 percent. The effective tax rate differs from the 21 percent federal statutory rate (as lowered by the Tax Act) on pretax income primarily due to ASU 2016-09, Compensation - Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting and state taxes, including state income tax credits in Indiana and Kansas.

Income tax expense for the quarter ended March 31, 2017 was $2,854, for an effective tax rate of 24.7 percent for the quarter. The effective tax rate differed from the 35 percent federal statutory rate on pretax income, primarily due to the impact of income tax benefits related to share-based compensation as accounted for in ASU 2016-09, Compensation - Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting, which was adopted by the Company during the quarter ended September 30, 2016, the domestic production activities deduction, and state taxes, including state income tax credits in Indiana and Kansas.