Supplementary Information On Natural Gas, Oil And NGL Reserves (Summary of Proved Developed and Undeveloped Reserves) (Details)	Sep. 30, 2021 bbl Mcf	Sep. 30, 2020 bbl Mcf	Sep. 30, 2019 bbl Mcf
Natural Gas [Member]
Reserve Quantities [Line Items]
Proved Developed Reserves (Volume) | Mcf	60,287,881	40,924,083	67,713,193
Proved Undeveloped Reserves (Volume) | Mcf	4,664,787	1,448,690	12,560,713
Oil [Member]
Reserve Quantities [Line Items]
Proved Developed Reserves (Volume)	1,439,860	1,148,989	1,863,096
Proved Undeveloped Reserves (Volume)	64,980	184,668	516,994
NGL [Member]
Reserve Quantities [Line Items]
Proved Developed Reserves (Volume)	1,467,092	1,135,864	1,747,242
Proved Undeveloped Reserves (Volume)	34,761	83,993	226,038