Commitments And Contingencies (Schedule of Delivery Commitments) (Details)	Dec. 31, 2020 bblPerDay mMBtus_per_day
Commitments and Contingencies Disclosure [Abstract]
2021 | mMBtus_per_day	264,671
2022 | mMBtus_per_day	275,000
2023 | mMBtus_per_day	279,178
2024 | mMBtus_per_day	264,754
2025 | mMBtus_per_day	125,000
Thereafter | mMBtus_per_day	405,822
Gas Delivery Commitment | mMBtus_per_day	1,614,425
2021 | bblPerDay	70,000
2022 | bblPerDay	30,575
2023 | bblPerDay	0
2024 | bblPerDay	0
2025 | bblPerDay	0
Thereafter | bblPerDay	0
Oil Delivery Commitment | bblPerDay	100,575