XML 45 R57.htm IDEA: XBRL DOCUMENT
v3.20.1

DERIVATIVE INSTRUMENTS - INCOME STATEMENT RELATED DISCLOSURES (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2020 | Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | $ 33,048 | $ 1,305 | $ 87,682 | $ (9,084)
Home Services and Other | Interest rate contracts | Interest Expense |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | 0 | (62) | 0 | (185)
Energy Services | Physical commodity contracts | Operating revenues |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | 12,096 | 171 | 21,932 | (1,361)
Energy Services | Physical commodity contracts | Gas purchases |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | (1,892) | 3,306 | (3,302) | (2,126)
Energy Services | Financial commodity contracts | Gas purchases |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | 23,319 | (2,231) | 69,412 | (5,187)
Energy Services | Foreign currency contracts | Gas purchases |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | (475) | 121 | (360) | (225)
Natural Gas Distribution |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | (17,917) | 279 | (18,165) | 7,652
Natural Gas Distribution | Physical commodity contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | 209 | 1,436 | 1,049 | 4,413
Natural Gas Distribution | Financial commodity contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | (11,434) | (1,157) | (12,522) | 3,239
Natural Gas Distribution | Interest rate contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of (losses) gains recognized in income on derivatives | $ (6,692) | $ 0 | $ (6,692) | $ 0

X
- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
Name: | us-gaap_DerivativeGainLossOnDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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_DerivativeInstrumentsGainLossLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_NondesignatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_SalesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=njr_GasPurchasesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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