IndexCertain Methane Gas Reserves, Proved Reserves, Carrying Amount (Deprecated 2018-01-31)
| Name | CertainMethaneGasReservesProvedReservesCarryingAmount |
|---|---|
| Namespace | http://fasb.org/us-gaap/2020-01-31 |
| Prefix | us-gaap |
| Data type | xbrli:monetaryItemType |
| Period type | instant |
| Substitution Group | xbrli:item |
| Balance | debit |
| Nillable | True |
| Abstract | False |
Labels
| Text | Lang | Role | Container role |
|---|---|---|---|
| The carrying amount of proved reserves related to methane gas that are deemed to be economically producible only as a consequence of existing Federal tax incentives. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Certain Methane Gas Reserves, Proved Reserves, Carrying Amount (Deprecated 2018-01-31) | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |