v3.21.1

Revenue from Contracts With Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 559,200	$ 458,300
Revenue from alternative revenue programs	21,600	40,600
Other	1,700	2,800
Total revenue from other sources	23,300	43,400
Total Operating Revenue	582,496	501,735
Gas and transportation sales \| Gas sold and delivered
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	442,600	346,300
Gas and transportation sales \| Gas delivered for others
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	102,900	97,600
Gas and transportation sales \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	12,800	13,700
Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 900	$ 700

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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WASHINGTON GAS LIGHT CO 10-Q