REGULATORY ENVIRONMENT - PGL (Details)	Mar. 31, 2021 Assurance
Illinois Commerce Commission (ICC) \| PGL
Public Utilities, General Disclosures [Line Items]
Amount of assurance that PGL's QIP rider costs will be recoverable	0

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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