Related Party Transactions (Other Revenue and Expense) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Duke Energy Carolinas | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 193	$ 207	$ 590	$ 653
Duke Energy Carolinas | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	7	6	21	18
Duke Energy Carolinas | JDA | Duke Energy Progress
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	210	68	477	133
Related party transaction, other revenues from transactions with related party	16	6	54	32
Duke Energy Carolinas | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	5	14	14	43
Progress Energy | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	188	201	568	615
Progress Energy | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	10	10	32	31
Progress Energy | JDA | Duke Energy Carolinas
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	16	6	54	32
Related party transaction, other revenues from transactions with related party	210	68	477	133
Progress Energy | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	19	19	57	56
Duke Energy Progress | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	111	121	338	367
Duke Energy Progress | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	5	4	15	14
Duke Energy Progress | JDA | Duke Energy Carolinas
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	16	6	54	32
Related party transaction, other revenues from transactions with related party	210	68	477	133
Duke Energy Progress | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	19	19	57	56
Duke Energy Florida | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	77	80	230	248
Duke Energy Florida | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	5	6	17	17
Duke Energy Ohio | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	87	79	251	237
Duke Energy Ohio | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	2	1	4	3
Duke Energy Indiana | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	115	96	330	302
Duke Energy Indiana | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	2	2	6	6
Piedmont | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	37	32	109	101
Piedmont | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	1	1	2	3
Piedmont | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, other revenues from transactions with related party	24	33	71	99
Piedmont | Natural gas storage and transportation costs | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 6	$ 6	$ 17	$ 17