Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Allowance for doubtful accounts - receivables	$ 27	$ 22
Regulatory Assets: Current	1,637	1,796
Current Assets: Other	505	764
Other Noncurrent Assets: Regulatory assets	13,264	13,222
Other, noncurrent assets	3,539	3,289
Current maturities of long-term debt	4,669	3,141
Long-Term Debt	$ 56,049	$ 54,985
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized	2,000,000,000	2,000,000,000
Common stock, shares outstanding	736,000,000	733,000,000
Other, noncurrent liabilities	$ 1,773	$ 1,581
Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	106	54
Regulatory Assets: Current	53	52
Current Assets: Other	335	242
Other Noncurrent Assets: Regulatory assets	951	989
Other, noncurrent assets	90	110
Current maturities of long-term debt	466	216
Long-Term Debt	3,628	3,997
Other, noncurrent liabilities	342	228
Duke Energy Carolinas
Allowance for doubtful accounts - receivables	1	3
Regulatory Assets: Current	495	550
Current Assets: Other	44	21
Other Noncurrent Assets: Regulatory assets	3,400	3,360
Other, noncurrent assets	1,179	1,149
Current maturities of long-term debt	751	458
Long-Term Debt	11,497	11,142
Other, noncurrent liabilities	644	627
Duke Energy Carolinas | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	21	7
Progress Energy
Allowance for doubtful accounts - receivables	9	7
Regulatory Assets: Current	775	946
Current Assets: Other	81	210
Other Noncurrent Assets: Regulatory assets	6,270	6,346
Other, noncurrent assets	1,212	1,049
Current maturities of long-term debt	1,726	1,577
Long-Term Debt	$ 17,989	$ 17,907
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized	100	100
Common stock, shares outstanding	100	100
Other, noncurrent liabilities	$ 443	$ 383
Progress Energy | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	28	9
Regulatory Assets: Current	53	52
Current Assets: Other	16	39
Other Noncurrent Assets: Regulatory assets	951	989
Current maturities of long-term debt	305	54
Long-Term Debt	1,351	1,632
Duke Energy Progress
Allowance for doubtful accounts - receivables	4	3
Regulatory Assets: Current	472	526
Current Assets: Other	54	60
Other Noncurrent Assets: Regulatory assets	4,449	4,152
Other, noncurrent assets	720	651
Current maturities of long-term debt	603	1,006
Long-Term Debt	8,605	7,902
Other, noncurrent liabilities	88	92
Duke Energy Progress | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	17	5
Duke Energy Florida
Allowance for doubtful accounts - receivables	5	3
Regulatory Assets: Current	303	419
Current Assets: Other	25	58
Other Noncurrent Assets: Regulatory assets	1,821	2,194
Other, noncurrent assets	341	311
Current maturities of long-term debt	623	571
Long-Term Debt	7,294	7,416
Other, noncurrent liabilities	205	136
Duke Energy Florida | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	11	4
Regulatory Assets: Current	53	52
Current Assets: Other	16	39
Other Noncurrent Assets: Regulatory assets	951	989
Current maturities of long-term debt	305	54
Long-Term Debt	1,001	1,307
Duke Energy Ohio
Allowance for doubtful accounts - receivables	5	4
Regulatory Assets: Current	35	49
Current Assets: Other	13	21
Other Noncurrent Assets: Regulatory assets	597	549
Other, noncurrent assets	62	52
Long-Term Debt	$ 3,064	$ 2,594
Common stock, par value (in usd per share)	$ 8.50	$ 8.50
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares outstanding	90,000,000	90,000,000
Other, noncurrent liabilities	$ 100	$ 94
Duke Energy Indiana
Allowance for doubtful accounts - receivables	3	3
Regulatory Assets: Current	119	90
Current Assets: Other	30	60
Other Noncurrent Assets: Regulatory assets	1,184	1,082
Other, noncurrent assets	228	234
Current maturities of long-term debt	13	503
Long-Term Debt	3,941	3,404
Other, noncurrent liabilities	56	18
Piedmont Natural Gas
Allowance for doubtful accounts - receivables	9	6
Regulatory Assets: Current	119	73
Current Assets: Other	51	28
Other Noncurrent Assets: Regulatory assets	287	290
Other, noncurrent assets	279	121
Current maturities of long-term debt	160
Long-Term Debt	$ 2,620	$ 2,384
Common stock, shares authorized	100	100
Common stock, shares outstanding	100	100
Other, noncurrent liabilities	$ 146	$ 148
Preferred stock, Series A
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, depositary shares authorized	40,000,000	40,000,000
Preferred stock, depositary shares outstanding	40,000,000	40,000,000
Preferred stock, Series B
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, depositary shares authorized	1,000,000	1,000,000
Preferred stock, depositary shares outstanding	1,000,000	1,000,000