| **Income Taxes**                     | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
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| **Income Tax Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Income Tax Disclosure                | INCOME TAXESWe evaluate our estimated annual effective income tax rate on a quarterly basis based on current and forecasted operating results and tax laws. The estimated annual effective tax rate is adjusted quarterly based upon actual results and updated operating forecasts. Consequently, based upon the mix and timing of our actual earnings compared to annual projections, our effective tax rate may vary quarterly and may make quarterly comparisons not meaningful. A tax expense or benefit unrelated to the current year income or loss is recognized in its entirety as a discrete item of tax in the period identified. The quarterly income tax provision is generally comprised of tax expense on income or tax benefit on loss at the most recent estimated annual effective tax rate, adjusted for the effect of discrete items.The effective tax rate for continuing operations for the three and nine months ended September 30, 2013 was a 40.0% and 36.6%, respectively, benefit on loss compared to a 35.3% and 31.1% benefit on loss for the three and nine months ended September 30, 2012, respectively. The effective tax rates for the three and nine months ended September 30, 2013 differ from the statutory rate primarily due to net permanent additions, largely nondeductible officers' compensation, partially offset by percentage depletion deductions. The effective tax rates for the three and nine months ended September 30, 2012 differ from the statutory rate primarily due to net permanent deductions, largely percentage depletion, partially offset by nondeductible officer's compensation. There were no significant discrete items recorded during the three and nine months ended September 30, 2013 or 2012.As of September 30, 2013, we had a gross liability for unrecognized tax benefits of $0.2 million, unchanged from the amount recorded at December 31, 2012. If recognized, this liability would affect our effective tax rate. This liability is reflected in other accrued expenses on our accompanying condensed consolidated balance sheets. We expect our remaining liability for uncertain tax positions to decrease in the next twelve months due to the expiration of the statute of limitations. As of the date of this report, we are current with our income tax filings in all applicable state jurisdictions. We have received notice from the State of Colorado that our 2008 through current state income tax returns have been selected for audit. |

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| - Definition
The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.
+ References
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