Income Taxes	6 Months Ended
Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The income tax provision includes U.S. federal, state and local, and foreign income taxes and is based on the application of a forecasted annual income tax rate applied to the current quarter's year-to-date pre-tax income or loss. In determining the estimated annual effective income tax rate, the Company analyzes various factors, including projections of the Company's annual earnings, taxing jurisdictions in which the earnings will be generated, the impact of state and local income taxes, the Company's ability to use tax credits and net operating loss carryforwards, and available tax planning alternatives. Discrete items, including the effect of changes in tax laws, tax rates and certain circumstances with respect to valuation allowances or other unusual or non-recurring tax adjustments are reflected in the period in which they occur as an addition to, or reduction from, the income tax provision, rather than included in the estimated effective annual income tax rate. The Company's effective income tax rate is affected by the benefit of percentage depletion. In the second quarter and six months ended June 30, 2016, the Company recorded an income tax benefit of $2.3 million as a result of the reversal of an uncertain tax position recorded as part of the Centennial acquisition. The Company also reversed a corresponding indemnification receivable related to the uncertain tax position that resulted in $2.2 million of other expense, included on the line "Other, net, including interest income," in the second quarter and six months ended June 30, 2016.

Income Taxes

6 Months Ended

Jun. 30, 2016

The income tax provision includes U.S. federal, state and local, and foreign income taxes and is based on the application of a forecasted annual income tax rate applied to the current quarter's year-to-date pre-tax income or loss. In determining the estimated annual effective income tax rate, the Company analyzes various factors, including projections of the Company's annual earnings, taxing jurisdictions in which the earnings will be generated, the impact of state and local income taxes, the Company's ability to use tax credits and net operating loss carryforwards, and available tax planning alternatives. Discrete items, including the effect of changes in tax laws, tax rates and certain circumstances with respect to valuation allowances or other unusual or non-recurring tax adjustments are reflected in the period in which they occur as an addition to, or reduction from, the income tax provision, rather than included in the estimated effective annual income tax rate. The Company's effective income tax rate is affected by the benefit of percentage depletion.

In the second quarter and six months ended June 30, 2016, the Company recorded an income tax benefit of $2.3 million as a result of the reversal of an uncertain tax position recorded as part of the Centennial acquisition. The Company also reversed a corresponding indemnification receivable related to the uncertain tax position that resulted in $2.2 million of other expense, included on the line "Other, net, including interest income," in the second quarter and six months ended June 30, 2016.