Investments in Debt and Equity Securities (Estimated Fair Value of Investments in Debt and Equity Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale
Estimated Fair Value	$ 3,326
Total Investments
Unrealized Holding Gains	5,804	$ 5,019
Unrealized Holding Losses	219	171
Estimated Fair Value	11,905	10,603
NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	5,753	4,942
Gross Unrealized Holding Losses	61	22
Estimated Fair Value	8,233	7,278
Debt Securities, Available-for-sale
Estimated Fair Value	3,060	2,732
Total Investments
Unrealized Holding Gains	5,765	4,985
Unrealized Holding Losses	200	159
Estimated Fair Value	11,432	10,143
NDTF | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	139	133
NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	6	12
Gross Unrealized Holding Losses	33	43
Estimated Fair Value	673	632
NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	6
Gross Unrealized Holding Losses	14	16
Estimated Fair Value	342	347
NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	3	24
Gross Unrealized Holding Losses	84	65
Estimated Fair Value	1,806	1,575
NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	1
Gross Unrealized Holding Losses	8	13
Estimated Fair Value	239	178
Other Investments
Equity Securities, FV-NI
Gross Unrealized Holding Gains	39	33
Gross Unrealized Holding Losses	4
Estimated Fair Value	160	158
Debt Securities, Available-for-sale
Estimated Fair Value	266	271
Total Investments
Unrealized Holding Gains	39	34
Unrealized Holding Losses	19	12
Estimated Fair Value	473	460
Other Investments | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	47	31
Other Investments | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	5	6
Estimated Fair Value	79	82
Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Gross Unrealized Holding Losses	1	2
Estimated Fair Value	83	77
Other Investments | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	5	2
Estimated Fair Value	59	65
Other Investments | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	4	2
Estimated Fair Value	45	47
Duke Energy Carolinas
Debt Securities, Available-for-sale
Estimated Fair Value	1,651
Duke Energy Carolinas | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	3,386	2,886
Gross Unrealized Holding Losses	33	14
Estimated Fair Value	4,751	4,196
Debt Securities, Available-for-sale
Estimated Fair Value	1,651	1,438
Total Investments
Unrealized Holding Gains	3,389	2,904
Unrealized Holding Losses	122	99
Estimated Fair Value	6,464	5,685
Duke Energy Carolinas | NDTF | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	62	51
Duke Energy Carolinas | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	4
Gross Unrealized Holding Losses	27	35
Estimated Fair Value	401	390
Duke Energy Carolinas | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	4	4
Estimated Fair Value	36	50
Duke Energy Carolinas | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		13
Gross Unrealized Holding Losses	50	33
Estimated Fair Value	991	826
Duke Energy Carolinas | NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	1
Gross Unrealized Holding Losses	8	13
Estimated Fair Value	223	172
Progress Energy
Debt Securities, Available-for-sale
Estimated Fair Value	1,433
Total Investments
Unrealized Holding Gains	2,376	2,081
Unrealized Holding Losses	78	61
Estimated Fair Value	5,015	4,499
Progress Energy | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	2,367	2,056
Gross Unrealized Holding Losses	28	8
Estimated Fair Value	3,482	3,082
Debt Securities, Available-for-sale
Estimated Fair Value	1,409	1,294
Total Investments
Unrealized Holding Gains	2,376	2,081
Unrealized Holding Losses	78	60
Estimated Fair Value	4,968	4,458
Progress Energy | NDTF | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	77	82
Progress Energy | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	4	8
Gross Unrealized Holding Losses	6	8
Estimated Fair Value	272	242
Progress Energy | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	6
Gross Unrealized Holding Losses	10	12
Estimated Fair Value	306	297
Progress Energy | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	3	11
Gross Unrealized Holding Losses	34	32
Estimated Fair Value	815	749
Progress Energy | NDTF | Other debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	16	6
Progress Energy | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	24	23
Total Investments
Unrealized Holding Losses		1
Estimated Fair Value	47	41
Progress Energy | Other Investments | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	23	18
Progress Energy | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses		1
Estimated Fair Value	24	23
Duke Energy Progress
Debt Securities, Available-for-sale
Estimated Fair Value	1,221
Total Investments
Unrealized Holding Gains	2,265	1,979
Unrealized Holding Losses	70	46
Estimated Fair Value	4,653	4,089
Duke Energy Progress | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	2,256	1,956
Gross Unrealized Holding Losses	28	8
Estimated Fair Value	3,362	2,970
Debt Securities, Available-for-sale
Estimated Fair Value	1,221	1,050
Total Investments
Unrealized Holding Gains	2,265	1,979
Unrealized Holding Losses	70	46
Estimated Fair Value	4,637	4,075
Duke Energy Progress | NDTF | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	54	55
Duke Energy Progress | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	4	7
Gross Unrealized Holding Losses	6	8
Estimated Fair Value	256	229
Duke Energy Progress | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	6
Gross Unrealized Holding Losses	10	12
Estimated Fair Value	306	297
Duke Energy Progress | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	3	10
Gross Unrealized Holding Losses	26	18
Estimated Fair Value	645	518
Duke Energy Progress | NDTF | Other debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	14	6
Duke Energy Progress | Other Investments
Total Investments
Estimated Fair Value	16	14
Duke Energy Progress | Other Investments | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	16	14
Duke Energy Florida
Debt Securities, Available-for-sale
Estimated Fair Value	212
Total Investments
Unrealized Holding Gains	111	102
Unrealized Holding Losses	8	15
Estimated Fair Value	358	409
Duke Energy Florida | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	111	100
Estimated Fair Value	120	112
Debt Securities, Available-for-sale
Estimated Fair Value	188	244
Total Investments
Unrealized Holding Gains	111	102
Unrealized Holding Losses	8	14
Estimated Fair Value	331	383
Duke Energy Florida | NDTF | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	23	27
Duke Energy Florida | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Estimated Fair Value	16	13
Duke Energy Florida | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Gross Unrealized Holding Losses	8	14
Estimated Fair Value	170	231
Duke Energy Florida | NDTF | Other debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	2
Duke Energy Florida | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	24	23
Total Investments
Unrealized Holding Losses		1
Estimated Fair Value	27	26
Duke Energy Florida | Other Investments | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	3	3
Duke Energy Florida | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses		1
Estimated Fair Value	24	23
Duke Energy Indiana
Debt Securities, Available-for-sale
Estimated Fair Value	56
Total Investments
Unrealized Holding Gains		5
Unrealized Holding Losses	5	1
Estimated Fair Value	146	163
Duke Energy Indiana | Other Investments
Equity Securities, FV-NI
Gross Unrealized Holding Gains		4
Gross Unrealized Holding Losses	4
Estimated Fair Value	89	98
Debt Securities, Available-for-sale
Estimated Fair Value	56	64
Duke Energy Indiana | Other Investments | Cash and cash equivalents
Cash and Cash Equivalents
Estimated Fair Value	1	1
Duke Energy Indiana | Other Investments | Corporate debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	6	8
Duke Energy Indiana | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Gross Unrealized Holding Losses	1	1
Estimated Fair Value	43	46
Duke Energy Indiana | Other Investments | U.S. government bonds
Debt Securities, Available-for-sale
Estimated Fair Value	$ 7	$ 10