Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Net cash paid for capitalized interest	$ 55	$ 61
ALABAMA POWER CO
Net cash paid for capitalized interest	6	7
GEORGIA POWER CO
Net cash paid for capitalized interest	11	10
GULF POWER CO
Net cash paid for capitalized interest	0	0
MISSISSIPPI POWER CO
Interest paid	53	49
Net cash paid for capitalized interest	27	23
SOUTHERN POWER CO
Net cash paid for capitalized interest	4	21
SOUTHERN Co GAS
Net cash paid for capitalized interest	$ 7
Predecessor | SOUTHERN Co GAS
Net cash paid for capitalized interest		$ 3