Asset Retirement Obligations (ARO Rollforward) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	$ 12,776
Accretion expense	376
Liabilities settled	(488)
Revision in estimates of cash flows	286
Balance at end of period	12,950
Duke Energy Carolinas
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	5,301
Accretion expense	180
Liabilities settled	(163)
Revision in estimates of cash flows	75
Balance at end of period	5,393
Progress Energy
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	6,112
Accretion expense	170
Liabilities settled	(239)
Revision in estimates of cash flows	160
Balance at end of period	6,203
Duke Energy Progress
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	5,675
Accretion expense	159
Liabilities settled	(160)
Revision in estimates of cash flows	165
Balance at end of period	5,839
Duke Energy Florida
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	437
Accretion expense	11
Liabilities settled	(79)
Revision in estimates of cash flows	(5)
Balance at end of period	364
Duke Energy Ohio
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	136
Accretion expense	4
Liabilities settled	(8)
Revision in estimates of cash flows	23
Balance at end of period	155
Duke Energy Indiana
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	987
Accretion expense	21
Liabilities settled	(77)
Revision in estimates of cash flows	27
Balance at end of period	958
Piedmont
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	22
Accretion expense	1
Balance at end of period	$ 23