Operating Revenue (Operating Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Electric sales:
Regulated									$ 7,482		$ 7,460		$ 7,193
Nonregulated									1,488		1,839		2,511
Gas sales:
Regulated									218		334		323
Nonregulated									471		751		930
Gas transportation and storage									1,616		1,543		1,535
Other									408		509		628
Total operating revenue	$ 2,556	$ 2,971	$ 2,747	$ 3,409	$ 2,943	$ 3,050	$ 2,813	$ 3,630	11,683		12,436		13,120
Virginia Electric and Power Company
Electric sales:
Regulated									7,482		7,460		7,193
Gas sales:
Other									140		119		102
Total operating revenue	1,614	2,058	1,813	2,137	1,814	2,053	1,729	1,983	7,622	[1]	7,579	[1]	7,295	[1]
Dominion Gas Holdings, LLC
Gas sales:
Regulated									122		209		202
Nonregulated									10		26		32
Gas transportation and storage									1,366		1,353		1,338
NGL revenue									93		212		292
Other									125		98		73
Total operating revenue	$ 425	$ 365	$ 395	$ 531	$ 510	$ 391	$ 428	$ 569	$ 1,716	[2]	$ 1,898	[2]	$ 1,937	[2]

[1] See Note 24 for amounts attributable to affiliates.

[2] See Note 24 for amounts attributable to related parties.