Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Effective tax rate	3.00%	0.00%	(15.00%)
Operating loss carryforward valuation allowance	$ 29,000,000
Unrecognized tax benefits that would impact effective tax rate	0
Statutory depletion carryforward
Income Taxes [Line Items]
Tax credit carryforward	13,000,000
Interest deduction carryforward
Income Taxes [Line Items]
Tax credit carryforward	177,000,000
Exploration Program in Canada
Income Taxes [Line Items]
Net operating loss carryforward	29,000,000
Indigo Merger
Income Taxes [Line Items]
Operating loss carryforwards subject to a section 382 limitation	48,000,000
Montage Merger
Income Taxes [Line Items]
Operating loss carryforwards subject to a section 382 limitation	1,700,000
Net operating loss carryforward	858,000,000
Federal
Income Taxes [Line Items]
Income taxes paid	35,700,000
Income tax refund received			$ 32,000,000
Operating loss carryforwards subject to a section 382 limitation	2,000,000,000
Net operating loss carryforward	4,000,000,000
Operating loss carryforwards, subject to expiration	3,000,000,000
Operating loss carryforwards, not subject to expiration	1,000,000,000
Statel
Income Taxes [Line Items]
Income taxes paid	$ 5,300,000