Regulatory Matters (Regulatory Matters Narrative - Piedmont) (Details) - 2022 South Carolina Rate Case - PSCSC - Piedmont $ in Millions	Apr. 01, 2022 USD ($)
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount	$ 7
Requested rate increase, percentage, net of tax	3.40%

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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