REGULATORY MATTERS - Nuclear Construction Joint Owner Contracts (Details)	Aug. 31, 2018
Georgia Power \| Plant Vogtle Units 3 And 4
Loss Contingencies [Line Items]
Ownership interest percentage required for voting for continuing construction	90.00%

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.

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration