CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net Income (Loss) Attributable to Parent	$ (1,109)	$ 124
SCEG
Other Comprehensive Income (Loss)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(1,103)	128		$ 262	$ 280
Genco
Other Comprehensive Income (Loss)
Less comprehensive income attributable to noncontrolling interest	(6)		$ (4)	15	10
SCE&G (including Fuel Company)
Net Income (Loss) Attributable to Parent [Abstract]
Net Income (Loss) Available to Common Stockholders, Basic	(1,109)	$ 124
Other Comprehensive Income (Loss)
Comprehensive income available to common shareholder	$ (1,109)		$ 124	$ 247	$ 270