Stock-Based Compensation, Dividend Restrictions, And Calculations Of Earnings Per Share Of Common Stock (Narrative) (Details) (USD $)	1 Months Ended	12 Months Ended					1 Months Ended	12 Months Ended
	Sep. 30, 2007	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009	Sep. 30, 2010	Sep. 30, 2009	Jan. 31, 2009 Conectiv, LLC [Member]	Dec. 31, 2011 Time-Based Restricted Stock [Member]	Dec. 31, 2010 Time-Based Restricted Stock [Member]	Dec. 31, 2009 Time-Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized for issuance		10,000,000
Stock-based compensation expense		$ 0	$ 0	$ 0				$ 6,000,000	$ 5,000,000	$ 5,000,000
Requisite service period (years)		three
Eligible percentage of common stock over the performance period target award minimum		0.00%
Costs recognized, weighted average period (years)		2
Eligible percentage of common stock over the performance period target award maximum		200.00%
Stock options granted subsequent to May 2002		0
Number of shares of common stock non-employee directors are entitled		1,000
Stock option expiration (years)		10
Vesting period, minimum (years)	two						5
Vesting period, maximum (years)	three						7
Targeted performance criteria		100.00%
Shares outstanding and vested					3,606	5,409	6,669
Restricted stock granted	9,015
Unrecognized compensation expense		9,000,000
Deferred compensation balance		1,000,000	1,000,000
Ratio of equity to total capitalization		30.00%
Retained earnings		1,072,000,000	1,059,000,000
Shares issued and sold under the DRP		2,000,000	2,000,000	2,000,000
Purchases of common stock minimum per calendar month		25
Purchases of common stock maximum per calendar year		$ 200,000