Investments in Debt and Equity Securities (Estimated Fair Value of Investments in Debt and Equity Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale
Estimated Fair Value	$ 2,815
Total Investments
Unrealized Holding Gains	3,682	$ 5,033
Unrealized Holding Losses	395	66
Estimated Fair Value	9,051	10,893
NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	3,658	4,905
Gross Unrealized Holding Losses	105	43
Estimated Fair Value	5,871	7,350
Debt Securities, Available-for-sale
Estimated Fair Value	2,550	2,891
Total Investments
Unrealized Holding Gains	3,661	4,992
Unrealized Holding Losses	359	63
Estimated Fair Value	8,636	10,401
NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	215	160
NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	39
Gross Unrealized Holding Losses	85	6
Estimated Fair Value	641	829
NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		14
Gross Unrealized Holding Losses	39	1
Estimated Fair Value	330	314
NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	31
Gross Unrealized Holding Losses	112	12
Estimated Fair Value	1,423	1,568
NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		3
Gross Unrealized Holding Losses	18	1
Estimated Fair Value	156	180
Other Investments
Equity Securities, FV-NI
Gross Unrealized Holding Gains	21	36
Gross Unrealized Holding Losses	16
Estimated Fair Value	128	156
Debt Securities, Available-for-sale
Estimated Fair Value	265	300
Total Investments
Unrealized Holding Gains	21	41
Unrealized Holding Losses	36	3
Estimated Fair Value	415	492
Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	22	36
Other Investments | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		2
Gross Unrealized Holding Losses	12	1
Estimated Fair Value	84	119
Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		3
Gross Unrealized Holding Losses	3	1
Estimated Fair Value	78	80
Other Investments | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	2
Estimated Fair Value	62	56
Other Investments | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	3	1
Estimated Fair Value	41	45
Duke Energy Carolinas
Debt Securities, Available-for-sale
Estimated Fair Value	1,298
Duke Energy Carolinas | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	2,147	2,887
Gross Unrealized Holding Losses	51	19
Estimated Fair Value	3,367	4,265
Debt Securities, Available-for-sale
Estimated Fair Value	1,298	1,441
Total Investments
Unrealized Holding Gains	2,149	2,932
Unrealized Holding Losses	192	27
Estimated Fair Value	4,782	5,759
Duke Energy Carolinas | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	117	53
Duke Energy Carolinas | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	24
Gross Unrealized Holding Losses	62	4
Estimated Fair Value	401	506
Duke Energy Carolinas | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		2
Gross Unrealized Holding Losses	10
Estimated Fair Value	64	48
Duke Energy Carolinas | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	16
Gross Unrealized Holding Losses	51	3
Estimated Fair Value	685	712
Duke Energy Carolinas | NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	0	3
Gross Unrealized Holding Losses	18	1
Estimated Fair Value	148	175
Progress Energy
Debt Securities, Available-for-sale
Estimated Fair Value	1,277
Total Investments
Unrealized Holding Gains	1,512	2,062
Unrealized Holding Losses	167	36
Estimated Fair Value	3,890	4,688
Progress Energy | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	1,511	2,018
Gross Unrealized Holding Losses	54	24
Estimated Fair Value	2,504	3,085
Debt Securities, Available-for-sale
Estimated Fair Value	1,252	1,450
Total Investments
Unrealized Holding Gains	1,512	2,060
Unrealized Holding Losses	167	36
Estimated Fair Value	3,854	4,642
Progress Energy | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	98	107
Progress Energy | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		15
Gross Unrealized Holding Losses	23	2
Estimated Fair Value	240	323
Progress Energy | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		12
Gross Unrealized Holding Losses	29	1
Estimated Fair Value	266	266
Progress Energy | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	15
Gross Unrealized Holding Losses	61	9
Estimated Fair Value	738	856
Progress Energy | NDTF | Other debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	8	5
Progress Energy | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	25	26
Total Investments
Unrealized Holding Gains		2
Estimated Fair Value	36	46
Progress Energy | Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	11	20
Progress Energy | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		2
Estimated Fair Value	25	26
Duke Energy Progress
Debt Securities, Available-for-sale
Estimated Fair Value	963
Total Investments
Unrealized Holding Gains	1,432	1,957
Unrealized Holding Losses	142	29
Estimated Fair Value	3,439	4,105
Duke Energy Progress | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	1,431	1,915
Gross Unrealized Holding Losses	54	23
Estimated Fair Value	2,411	2,970
Debt Securities, Available-for-sale
Estimated Fair Value	963	1,025
Total Investments
Unrealized Holding Gains	1,432	1,957
Unrealized Holding Losses	142	29
Estimated Fair Value	3,430	4,089
Duke Energy Progress | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	56	94
Duke Energy Progress | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		15
Gross Unrealized Holding Losses	22	2
Estimated Fair Value	230	282
Duke Energy Progress | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		12
Gross Unrealized Holding Losses	29	1
Estimated Fair Value	266	266
Duke Energy Progress | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	15
Gross Unrealized Holding Losses	37	3
Estimated Fair Value	460	472
Duke Energy Progress | NDTF | Other debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	7	5
Duke Energy Progress | Other Investments
Total Investments
Estimated Fair Value	9	16
Duke Energy Progress | Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	9	16
Duke Energy Florida
Debt Securities, Available-for-sale
Estimated Fair Value	314
Total Investments
Unrealized Holding Gains	80	105
Unrealized Holding Losses	25	7
Estimated Fair Value	450	582
Duke Energy Florida | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	80	103
Gross Unrealized Holding Losses		1
Estimated Fair Value	93	115
Debt Securities, Available-for-sale
Estimated Fair Value	289	425
Total Investments
Unrealized Holding Gains	80	103
Unrealized Holding Losses	25	7
Estimated Fair Value	424	553
Duke Energy Florida | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	42	13
Duke Energy Florida | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	1
Estimated Fair Value	10	41
Duke Energy Florida | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	24	6
Estimated Fair Value	278	384
Duke Energy Florida | NDTF | Other debt securities
Debt Securities, Available-for-sale
Estimated Fair Value	1
Duke Energy Florida | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	25	26
Total Investments
Unrealized Holding Gains		2
Estimated Fair Value	26	29
Duke Energy Florida | Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	1	3
Duke Energy Florida | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		2
Estimated Fair Value	25	26
Duke Energy Indiana
Debt Securities, Available-for-sale
Estimated Fair Value	60
Total Investments
Unrealized Holding Gains	2	7
Unrealized Holding Losses	20	1
Estimated Fair Value	140	161
Duke Energy Indiana | Other Investments
Available-for-sale Securities
Cash and cash equivalents	1
Equity Securities, FV-NI
Gross Unrealized Holding Gains	2	6
Gross Unrealized Holding Losses	16
Estimated Fair Value	79	97
Debt Securities, Available-for-sale
Estimated Fair Value	60	64
Duke Energy Indiana | Other Investments | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	1
Estimated Fair Value	8	6
Duke Energy Indiana | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Gross Unrealized Holding Losses	3	1
Estimated Fair Value	45	46
Duke Energy Indiana | Other Investments | U.S. government bonds
Debt Securities, Available-for-sale
Estimated Fair Value	$ 7	$ 12