Contingencies - General Litigation Matters (Details) - MISSISSIPPI POWER CO - Kemper IGCC - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2016	Dec. 31, 2010
Loss Contingencies [Line Items]
DOE awards		$ 137	$ 270
Government grants received	$ 387

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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+ Details