XML 128 R132.htm IDEA: XBRL DOCUMENT v2.4.0.8
Related Party Transactions - Schedule of Related Party Transactions Included in Income Statement (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Delmarva Power & Light Co/De [Member]
     
Related Party Transaction [Line Items]      
Amounts of transaction       $ 1
Intercompany lease transactions 4 4 5
Atlantic City Electric Co [Member]
     
Related Party Transaction [Line Items]      
Amounts of transaction (4) (4) (4)
Intercompany use revenue $ 3 $ 3 $ 2