CONTINGENCIES, COMMITMENTS, AND GUARANTEES - APC Litigation (Details) - Alabama Power - AT&T $ in Millions	1 Months Ended
Apr. 30, 2019 USD ($)
Loss Contingencies [Line Items]
Potential refund amount owed	$ 87
Refund payment period	6 years

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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