Introduction - Nuclear Decommissioning (Details) - ALABAMA POWER CO - Plant Farley $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Decommissioning periods:
Beginning year	2037
Completion year	2076
Site study costs	$ 1,720
Radiated structures
Decommissioning periods:
Site study costs	1,621
Non-radiated structures
Decommissioning periods:
Site study costs	$ 99