Consolidated Statements of Cash Flows (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net cash paid for capitalized interest	$ 111,000	$ 92,000	$ 83,000
Alabama Power [Member]
Net cash paid for capitalized interest	18,000	11,000	7,000
Georgia Power [Member]
Net cash paid for capitalized interest	18,000	14,000	21,000
Gulf Power [Member]
Net cash paid for capitalized interest	5,373	3,421	2,500
Mississippi Power [Member]
Net cash paid for capitalized interest	68,679	54,118	32,816
Southern Power [Member]
Net cash paid for capitalized interest	$ (113)	$ 9,178	$ 19,092