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Rate and Regulatory Matters (Details) - USD ($) $ in Millions	1 Months Ended		6 Months Ended
	Jul. 31, 2015	Mar. 31, 2015	Jun. 30, 2015	Jul. 01, 2015
Regulatory Liabilities [Line Items]
Public Utilities Distribution System Improvement Charge			0.31%
Subsequent Event [Member]
Regulatory Liabilities [Line Items]
Public Utilities Distribution System Improvement Charge				0.37%
New Jersey Board of Public Utilities [Member]
Regulatory Liabilities [Line Items]
Originally filed increase in annual operating revenue		$ 9.5
Projected annual revenue			$ 0.1
New Jersey Board of Public Utilities [Member] | Subsequent Event [Member]
Regulatory Liabilities [Line Items]
Amended filed increase in annual operating revenue	$ 5.0
Delware Public Service Commission [Member] | Tidewater [Member]
Regulatory Liabilities [Line Items]
Projected annual revenue			$ 0.1

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- Definition

The projected annual revenue from new water operations.

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- Definition

The Distribution System Improvement Charge, or DISC, for public utilities.

+ References

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- Definition

Amount of public utility's amended requested rate increase (decrease) with regulatory agency.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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- 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.

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