Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 3,085	$ 2,865	$ 2,553
Duke Energy Progress [Member]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	715	599	566
Duke Energy Ohio [Member]
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 192	$ 228	$ 172