QUARTERLY FINANCIAL INFORMATION (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Regulated and Unregulated Operating Revenue	$ 956	$ 1,068	$ 967	$ 1,389	$ 1,214	$ 1,121	$ 1,026	$ 1,590	$ 4,380	$ 4,951	$ 4,495
Operating Income (Loss)	214	292	216	586	234	269	154	350	1,308	1,007	910
Income Available to Common Shareholders	$ 98	$ 149	$ 99	$ 400	$ 105	$ 144	$ 96	$ 193	$ 746	$ 538	471
Earnings Per Share, Basic and Diluted	$ 0.69	$ 1.04	$ 0.69	$ 2.80	$ 0.73	$ 1.01	$ 0.68	$ 1.37	$ 5.22	$ 3.79
SCE&G
Regulated Operating Revenue	$ 643	$ 806	$ 709	$ 772	$ 722	$ 812	$ 698	$ 859	$ 2,930	$ 3,091	2,845
Operating Income (Loss)	172	307	218	237	174	272	145	239	934	830	737
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	76	167	111	126	76	157	99	126	480	458	391
Net Income (Loss) Attributable to Parent	$ 73	$ 164	$ 107	$ 122	$ 73	$ 154	$ 96	$ 123	$ 466	$ 446	$ 380