Organization and Basis of Presentation (Schedule of Cash and Cash Equivalents) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Current Assets
Cash and cash equivalents	$ 336	$ 442
Other	106	141
Other Noncurrent Assets
Other	39	8
Total cash, cash equivalents and restricted cash	481	591	$ 427	$ 505
Progress Energy [Member]
Current Assets
Cash and cash equivalents	51	67
Other	31	39
Other Noncurrent Assets
Other	38	6
Total cash, cash equivalents and restricted cash	120	112	74	87
Duke Energy Florida [Member]
Current Assets
Cash and cash equivalents	16	36
Other	31	39
Other Noncurrent Assets
Total cash, cash equivalents and restricted cash	$ 47	$ 75	$ 45	$ 53