Regulatory Matters - Schedule of Current Base Rate Increase Requisition to Increase Annual Revenue (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended		1 Months Ended			0 Months Ended	6 Months Ended
	Mar. 26, 2014	Sep. 20, 2013	Mar. 31, 2014	Jul. 31, 2012	Dec. 31, 2011	Mar. 14, 2014 Atlantic City Electric Co [Member]	Jun. 30, 2014 Atlantic City Electric Co [Member]	Jun. 30, 2014 Atlantic City Electric Co [Member] NJ [Member]
Public Utilities, General Disclosures [Line Items]
Requested rate change	$ 23.40	$ 39.00	$ 61.70	$ 18.10		$ 61.70		$ 61.70
Return on equity, percentage	9.40%		10.25%	9.31%	10.75%	10.25%	10.80%	10.25%
Filing Date								Mar. 14, 2014
Expected Timing of Decision								Q1, 2015