Fair-Value Measurements (Placement of Assets and Liabilities Within the Fair Value Hierarchy Levels) (Details) - Recurring Fair Value Measures - Commodity Derivatives - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets Fair Value	$ 5,374	$ 1,238
Liabilities Fair Value	(10,431)	(11,061)
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets Fair Value	10,082	36,844
Liabilities Fair Value	(2,695)	(4,692)
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets Fair Value	0	0
Liabilities Fair Value	$ 0	$ 0