Fair-Value Measurements (Fair Value of Financial Assets Liabilities Measured on Recurring Basis) (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Level 1 | Commodity Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 1,238	$ 359
Liabilities	(11,061)	(2,589)
Level 1 | Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	0	0
Level 2 | Commodity Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	36,844	1,867
Liabilities	(4,692)	(608)
Level 2 | Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	0	0
Level 3 | Commodity Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Liabilities	0	0
Level 3 | Embedded Derivative Financial Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	$ 0	$ (83,210)