Regulatory Matters (Duke Energy Ohio - Exit Obligation Rollforward) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Public Utilities, General Disclosures [Line Items]
Regulatory assets	$ 18,130	$ 14,637
Restructuring Reserve [Roll Forward]
Balance, beginning of period	39	11
Cash Reductions	(8)	(8)
Balance, end of period	64	39
Duke Energy Ohio
Public Utilities, General Disclosures [Line Items]
Regulatory assets	$ 684	$ 707