Contingencies and Regulatory Matters - Table - SO Nuclear Construction (Details) - GEORGIA POWER CO - Plant Vogtle Units 3 And 4 $ in Billions	Dec. 31, 2017 USD ($)
Other Commitments [Line Items]
Project capital cost forecast	$ 7.3
Net investment as of December 31, 2017	3.4
Remaining estimate to complete	$ 3.9

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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