REGULATION - REGULATORY FILINGS (Details) - USD ($) $ in Millions	Mar. 31, 2017	Oct. 01, 2016
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