XML 69 R48.htm IDEA: XBRL DOCUMENT
v3.10.0.1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - PROPERTY PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
Public Utility, Property, Plant and Equipment [Line Items] |  |  |  |  |
Composite rate of depreciation |  |  | 2.29% | 2.25% | 2.32%
Depreciation and amortization |  |  | $ 85,701 | $ 81,841 | $ 72,748
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost |  |  | 3,304,491 | 3,211,070 |
Accumulated depreciation and amortization |  |  | (653,442) | (601,329) |
Property, plant and equipment, net |  |  | 2,651,049 | 2,609,741 |
Regulated Operation | Distribution facilities |  |  |  |  |
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost |  |  | $ 2,151,249 | 1,952,697 |
Regulated Operation | Distribution facilities | Minimum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 38 years |  |
Regulated Operation | Distribution facilities | Maximum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 74 years |  |
Regulated Operation | Transmission facilities |  |  |  |  |
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost |  |  | $ 295,692 | 294,586 |
Regulated Operation | Transmission facilities | Minimum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 35 years |  |
Regulated Operation | Transmission facilities | Maximum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 56 years |  |
Regulated Operation | Storage facilities |  |  |  |  |
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost |  |  | $ 79,470 | 78,245 |
Regulated Operation | Storage facilities | Minimum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 34 years |  |
Regulated Operation | Storage facilities | Maximum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 47 years |  |
Unregulated Operation | Solar property |  |  |  |  |
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost |  |  | $ 720,562 | 587,345 |
Unregulated Operation | Solar property | Minimum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 20 years |  |
Unregulated Operation | Solar property | Maximum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 25 years |  |
Unregulated Operation | Wind property |  |  |  |  |
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost | [1] |  | $ 0 | 244,764 |
Unregulated Operation | Wind property | Minimum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives | [1] |  | 17 years |  |
Unregulated Operation | Wind property | Maximum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives | [1] |  | 25 years |  |
Unregulated Operation | Midstream property |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives | [2] |  | 30 years |  |
Property, plant and equipment - wind equipment, at cost | [2] |  | $ 6,747 | 0 |
Unregulated Operation | All other property |  |  |  |  |
Property Classifications |  |  |  |  |
Property, plant and equipment - wind equipment, at cost |  |  | $ 50,771 | $ 53,433 |
Unregulated Operation | All other property | Minimum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 5 years |  |
Unregulated Operation | All other property | Maximum |  |  |  |  |
Property Classifications |  |  |  |  |
Estimated Useful Lives |  |  | 35 years |  |
September 2016 Base Rate Case |  |  |  |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |  |  |  |
Composite rate of depreciation |  | 2.40% |  |  |
[1] | Reclassified to assets held for sale. See Note 2. Summary of Significant Accounting Policies, for more information.
[2] | Includes activity related to the acquisition of IEC by Adelphia. For fiscal 2017, Midstream property was originally included in All other property.

X
- Definition Public Utilities, Property, Plant and Equipment, Approved Composite Depreciation Rate for Plants in Service + References No definition available. + Details
Name: | njr_PublicUtilitiesPropertyPlantandEquipmentApprovedCompositeDepreciationRateforPlantsinService
Namespace Prefix: | njr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.14) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
Name: | us-gaap_DepreciationDepletionAndAmortization
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PropertyPlantAndEquipmentGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(14)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(8)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Composite depreciation rate for public utility plants in service. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
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_PublicUtilityPropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=us-gaap_RegulatedOperationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_GasDistributionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_GasTransmissionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=njr_StorageFacilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=us-gaap_UnregulatedOperationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=njr_SolarPropertyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=njr_WindPropertyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=njr_MidstreamPropertyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_PropertyPlantAndEquipmentOtherTypesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=njr_September2016BaseRateCaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |