Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Sep. 01, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Cancellation of debt income not recognized for tax	$ 506,300
Reduction to Operating Loss Carryforward due to CODI	457,500
Reduction in tax basis for assets	$ 48,800
Valuation Allowance, Commentary	During the year ended December 31, 2019, in evaluating whether it was more likely than not that the company's deferred tax assets were realizable through future net income, we considered all available positive and negative evidence, including (i) our earnings history exclusive of the loss that created the future deductible amount coupled with evidence indicating that the loss is an aberration rather than a continuing condition, (ii) our ability to recover net operating loss carryforward deferred tax assets in future years, (iii) the existence of significant proved oil, NGL and natural gas reserves, (iv) future revenue and operating cost projections that indicate the company will produce more than enough taxable income to realize the deferred tax asset based on existing sales prices and cost structures and (vii) current market prices for oil, NGL and natural gas. Based on all the evidence available, we determined it was more likely than not that the deferred tax asset for net operating loss carryforwards were not fully realizable. As of December 31, 2019, a total valuation allowance of $19.7 million has been recorded.
Valuation allowance	$ 200,985		$ 19,654
Operating loss carryforwards	409,100	$ 726,400
Operating loss carryforwards subject to expiration	$ 223,000	$ 584,200
Operating loss carryforwards expiration	expire from 2021 to 2037