Income Tax Expense

9 Months Ended

Sep. 30, 2015

Income Tax Disclosure [Abstract]

Income Tax Expense

The effective tax rates for the three months ended September 30, 2015 and 2014 were 22.5% and 23.0%, respectively. The effective tax rates for the nine months ended September 30, 2015 and 2014 were both 22.7%. The change in tax expense for the three-month comparison is primarily the result of changes in activity levels among jurisdictions with different tax rates.