Operating Revenue

12 Months Ended

Dec. 31, 2020

Revenues [Abstract]

Operating Revenue

4.  OPERATING REVENUE

DESC’s operating revenue consists of the following:

Year Ended December 31,	2020				2019
(millions)	Electric		Gas		Electric		Gas
Customer class:
Residential	$	1,127	$	201	$	669	$	194
Commercial		746		103		507		111
Industrial		341		65		224		81
Other		123		18		116		18
Revenues from contracts with customers		2,337		387		1,516		404
Other revenues		15		—		9		—
Total Operating Revenues	$	2,352	$	387	$	1,525	$	404

Contract liabilities represent the obligation to transfer goods or services to a customer for which consideration has already been received from the customer. DESC had contract liability balances of $5 million and $9 million at December 31, 2020 and 2019, respectively. For the years ended December 31, 2020 and 2019, DESC recognized revenue of $6 million and $3 million from the beginning contract liability balances as DESC fulfilled its obligations to provide service to its customers. Contract liabilities are recorded in customer deposits and customer prepayments in the Consolidated Balance Sheets.

Contract Costs

Costs to obtain contracts are generally expensed when incurred. In limited instances, DESC provides economic development grants intended to support economic growth within DESC’s electric service territory and defers such grants as regulatory assets on the Consolidated Balance Sheets. Whenever these grants are contingent on a customer entering into a long-term electric supply contract with DESC, they are considered costs to obtain that underlying contract. Such costs that exceed certain thresholds are deferred and amortized on a straight-line basis over the term of the related service contract, which generally ranges from ten to 15 years.

Balances and activity related to contract costs deferred as regulatory assets were as follows:

	Regulatory Assets
(millions)	2020			2019
Beginning balance, January 1	$	13		$	15
Amortization		(1	)		(2	)
Ending balance, December 31	$	12		$	13