Property, Plant and Equipment (Narrative) (Detail) - Acquisition of Solar Project at Schools in Virginia $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) MW
Property Plant And Equipment [Line Items]
Anticipated projected cost \| $	$ 59
Aggregate generation capacity \| MW	29

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.

No definition available.

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