Revenue Recognition (Tables)

9 Months Ended

Sep. 30, 2020

Revenue From Contract With Customer [Abstract]

Disaggregation of Revenue

DESC has disaggregated operating revenues by customer class as follows:

	Three Months Ended				Three Months Ended				Nine Months Ended				Nine Months Ended
	September 30, 2020				September 30, 2019				September 30, 2020				September 30, 2019
(millions)	Electric		Gas		Electric		Gas		Electric		Gas		Electric		Gas
Customer class:
Residential	$	349	$	27	$	354	$	24	$	862	$	139	$	364	$	133
Commercial		216		18		229		19		568		71		296		80
Industrial		90		15		101		18		253		44		119		63
Other		33		4		37		6		90		12		82		13
Revenues from contracts with    customers		688		64		721		67		1,773		266		861		289
Other revenues		3		—		7		—		12		—		8		—
Total Operating Revenues	$	691	$	64	$	728	$	67	$	1,785	$	266	$	869	$	289