Investments in Debt and Equity Securities (Estimated Fair Value of Investments in Debt and Equity Securities) (Details) - USD ($)
$ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
$ 5,418
|
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
5,214
|
$ 6,153
|
| Gross Unrealized Holding Losses |
157
|
98
|
| Estimated Fair Value |
13,251
|
13,325
|
| NDTF |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
200
|
175
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
5,135
|
6,041
|
| Gross Unrealized Holding Losses |
37
|
14
|
| Estimated Fair Value |
7,269
|
8,519
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
5,171
|
4,193
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
5,160
|
6,096
|
| Gross Unrealized Holding Losses |
146
|
89
|
| Estimated Fair Value |
12,640
|
12,887
|
| Other Investments |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
229
|
53
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
54
|
57
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
135
|
139
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
247
|
246
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
54
|
57
|
| Gross Unrealized Holding Losses |
11
|
9
|
| Estimated Fair Value |
611
|
438
|
| Duke Energy Carolinas |
|
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
2,939
|
|
| Duke Energy Carolinas | NDTF |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
98
|
92
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
3,032
|
3,533
|
| Gross Unrealized Holding Losses |
19
|
10
|
| Estimated Fair Value |
4,175
|
4,896
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
2,939
|
2,349
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
3,044
|
3,561
|
| Gross Unrealized Holding Losses |
92
|
61
|
| Estimated Fair Value |
7,212
|
7,337
|
| Progress Energy |
|
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
2,257
|
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
2,116
|
2,535
|
| Gross Unrealized Holding Losses |
54
|
28
|
| Estimated Fair Value |
5,483
|
5,608
|
| Progress Energy | NDTF |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
102
|
83
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
2,103
|
2,508
|
| Gross Unrealized Holding Losses |
18
|
4
|
| Estimated Fair Value |
3,094
|
3,623
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
2,232
|
1,844
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
2,116
|
2,535
|
| Gross Unrealized Holding Losses |
54
|
28
|
| Estimated Fair Value |
5,428
|
5,550
|
| Progress Energy | Other Investments |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
30
|
34
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
25
|
24
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
55
|
58
|
| Duke Energy Progress |
|
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
2,105
|
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
1,994
|
2,406
|
| Gross Unrealized Holding Losses |
51
|
25
|
| Estimated Fair Value |
5,175
|
5,278
|
| Duke Energy Progress | NDTF |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
86
|
71
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
1,981
|
2,380
|
| Gross Unrealized Holding Losses |
18
|
4
|
| Estimated Fair Value |
2,962
|
3,485
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
2,105
|
1,698
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
1,994
|
2,406
|
| Gross Unrealized Holding Losses |
51
|
25
|
| Estimated Fair Value |
5,153
|
5,254
|
| Duke Energy Progress | Other Investments |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
22
|
24
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
22
|
24
|
| Duke Energy Florida |
|
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
152
|
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
122
|
129
|
| Gross Unrealized Holding Losses |
3
|
3
|
| Estimated Fair Value |
304
|
325
|
| Duke Energy Florida | NDTF |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
16
|
12
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
122
|
128
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
132
|
138
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
127
|
146
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
122
|
129
|
| Gross Unrealized Holding Losses |
3
|
3
|
| Estimated Fair Value |
275
|
296
|
| Duke Energy Florida | Other Investments |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
4
|
5
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
25
|
24
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
29
|
29
|
| Duke Energy Indiana |
|
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
29
|
|
| Duke Energy Indiana | Other Investments |
|
|
| Cash and Cash Equivalents |
|
|
| Estimated Fair Value |
1
|
|
| Equity Securities, FV-NI |
|
|
| Gross Unrealized Holding Gains |
5
|
6
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
51
|
53
|
| Debt Securities, Available-for-sale |
|
|
| Estimated Fair Value |
29
|
29
|
| Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract] |
|
|
| Gross Unrealized Holding Gains |
5
|
6
|
| Gross Unrealized Holding Losses |
1
|
1
|
| Estimated Fair Value |
81
|
82
|
| Corporate debt securities | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
6
|
17
|
| Gross Unrealized Holding Losses |
31
|
18
|
| Estimated Fair Value |
1,329
|
1,056
|
| Corporate debt securities | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
3
|
2
|
| Estimated Fair Value |
79
|
75
|
| Corporate debt securities | Duke Energy Carolinas | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
3
|
9
|
| Gross Unrealized Holding Losses |
24
|
15
|
| Estimated Fair Value |
846
|
662
|
| Corporate debt securities | Progress Energy | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
3
|
8
|
| Gross Unrealized Holding Losses |
7
|
3
|
| Estimated Fair Value |
483
|
394
|
| Corporate debt securities | Duke Energy Progress | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
3
|
8
|
| Gross Unrealized Holding Losses |
7
|
3
|
| Estimated Fair Value |
464
|
375
|
| Corporate debt securities | Duke Energy Florida | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
19
|
19
|
| Corporate debt securities | Duke Energy Indiana | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
1
|
1
|
| Municipal bonds | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
2
|
4
|
| Gross Unrealized Holding Losses |
16
|
13
|
| Estimated Fair Value |
370
|
366
|
| Municipal bonds | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
1
|
1
|
| Estimated Fair Value |
67
|
67
|
| Municipal bonds | Duke Energy Carolinas | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
6
|
5
|
| Estimated Fair Value |
46
|
42
|
| Municipal bonds | Progress Energy | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
2
|
4
|
| Gross Unrealized Holding Losses |
10
|
8
|
| Estimated Fair Value |
324
|
324
|
| Municipal bonds | Progress Energy | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
25
|
24
|
| Municipal bonds | Duke Energy Progress | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
2
|
4
|
| Gross Unrealized Holding Losses |
10
|
8
|
| Estimated Fair Value |
324
|
324
|
| Municipal bonds | Duke Energy Florida | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
25
|
24
|
| Municipal bonds | Duke Energy Indiana | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
1
|
1
|
| Estimated Fair Value |
25
|
25
|
| U.S. government bonds | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
15
|
31
|
| Gross Unrealized Holding Losses |
57
|
39
|
| Estimated Fair Value |
3,176
|
2,487
|
| U.S. government bonds | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
5
|
4
|
| Estimated Fair Value |
54
|
59
|
| U.S. government bonds | Duke Energy Carolinas | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
7
|
16
|
| Gross Unrealized Holding Losses |
38
|
26
|
| Estimated Fair Value |
1,808
|
1,403
|
| U.S. government bonds | Progress Energy | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
8
|
15
|
| Gross Unrealized Holding Losses |
19
|
13
|
| Estimated Fair Value |
1,368
|
1,084
|
| U.S. government bonds | Duke Energy Progress | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
8
|
14
|
| Gross Unrealized Holding Losses |
16
|
10
|
| Estimated Fair Value |
1,262
|
958
|
| U.S. government bonds | Duke Energy Florida | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
1
|
| Gross Unrealized Holding Losses |
3
|
3
|
| Estimated Fair Value |
106
|
126
|
| U.S. government bonds | Duke Energy Indiana | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
3
|
3
|
| Other debt securities | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
2
|
3
|
| Gross Unrealized Holding Losses |
5
|
5
|
| Estimated Fair Value |
296
|
284
|
| Other debt securities | Other Investments |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
2
|
2
|
| Estimated Fair Value |
47
|
45
|
| Other debt securities | Duke Energy Carolinas | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
2
|
3
|
| Gross Unrealized Holding Losses |
5
|
5
|
| Estimated Fair Value |
239
|
242
|
| Other debt securities | Progress Energy | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
57
|
42
|
| Other debt securities | Duke Energy Progress | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
55
|
41
|
| Other debt securities | Duke Energy Florida | NDTF |
|
|
| Debt Securities, Available-for-sale |
|
|
| Gross Unrealized Holding Gains |
0
|
0
|
| Gross Unrealized Holding Losses |
0
|
0
|
| Estimated Fair Value |
$ 2
|
$ 1
|