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REGULATION - REGULATORY FILINGS (Details) - Natural Gas Distribution $ in Millions | Mar. 29, 2019 USD ($) | Feb. 28, 2019 USD ($) project_component | Dec. 28, 2018 USD ($) | Dec. 18, 2018 USD ($)
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Schedule of Regulatory Filings [Line Items] |  |  |  |
Requested rate increase (decrease), amount | $ 128.2 |  |  |
Energy Efficiency EE |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Approved rate increase (decrease), amount |  |  |  | $ (8.8)
BGSS/CIP Filing |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Requested customer refunds, amount |  |  | $ 10.9 |
Infrastructure Investment Program (IIP) |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Program term |  | 5 years |  |
Number of project components | project_component |  | 2 |  |
Investment |  | $ 507.0 |  |
RAC |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Approved rate increase (decrease), amount | 1.4 |  |  |
NJCEP |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Approved rate increase (decrease), amount | 1.9 |  |  |
NJ RISE and SAFE II |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Requested rate | 8.7 |  |  |
Investment Cost | $ 75.0 |  |  |
BPU |  |  |  |
Schedule of Regulatory Filings [Line Items] |  |  |  |
Requested return on return, percentage | 7.87% |  |  |

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