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REGULATION - REGULATORY FILINGS (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Oct. 01, 2016
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Schedule of Regulatory Filings [Line Items] |  |
Increase in base tariff rates |  | $ 45.0
Return on equity |  | 9.75%
Public utilities, approved equity capital structure, percentage |  | 52.50%
Composite rate of depreciation |  | 2.40%
Recovery of expenditures, approved rolling period |  | 5 years
NJNG |  |
Schedule of Regulatory Filings [Line Items] |  |
Increase in base tariff rates | $ 4.3 |

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- Definition Public Utilities, Property, Plant and Equipment, Approved Composite Depreciation Rate for Plants in Service + References No definition available. + Details
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