XML 68 R55.htm IDEA: XBRL DOCUMENT
v3.22.2

DERIVATIVE INSTRUMENTS - VOLUME (Details) - Bcf | 9 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2022 | Sep. 30, 2021
Natural Gas Distribution | Long | Futures |  |
Derivative [Line Items] |  |
Notional amount | 27.3 | 22.2
Natural Gas Distribution | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | 8.1 | 7.6
Energy Services | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | (0.4) | 0.6
Energy Services | Short | Futures |  |
Derivative [Line Items] |  |
Notional amount | (5.1) | (13.4)
Energy Services | Short | Swaps |  |
Derivative [Line Items] |  |
Notional amount | (0.1) | (0.3)

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal volume used to calculate payments on a derivative instrument. + References No definition available. + Details
Name: | us-gaap_DerivativeNonmonetaryNotionalAmountVolume
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=njr_NaturalGasDistributionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PositionAxis=us-gaap_LongMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_FutureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_EnergyRelatedDerivativeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=njr_EnergyServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PositionAxis=us-gaap_ShortMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_SwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |