Income Taxes

9 Months Ended

Sep. 30, 2011

Income Taxes [Abstract]

Income Taxes

Note 6:        INCOME TAXES

Our effective tax rate for the nine months ended September 30, 2011 and 2010 was 28.6% and 24.4%, respectively. For both periods, the rate differs from the U.S. federal statutory rate of 35.0% largely due to depletion deductions, changes in tax reserves, differences in local tax rates on the income from our foreign subsidiaries, and the correction of an error in the nine months ended September 30, 2011, which was not material to our financial statements.

In the normal course of business, we are subject to examination by taxing authorities throughout the world. With few exceptions, we are no longer subject to income tax examinations by tax authorities for years prior to 2004. In general, the United States Internal Revenue Service ("IRS") has examined our federal income tax returns for all years through 2009.