Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Allowance for doubtful accounts - receivables	$ 22	$ 16
Regulatory Assets: Current	1,796	2,005
Current Assets: Other	764	1,049
Other Noncurrent Assets: Regulatory assets	13,222	13,617
Other Noncurrent Assets: Other	3,289	2,935
Current maturities of long-term debt	3,141	3,406
Long-Term Debt	54,985	51,123
Other Noncurrent Liabilities: Other	$ 1,581	$ 1,650
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	2,000,000,000	2,000,000,000
Common stock, shares outstanding	733,000,000	727,000,000
Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	$ 54	$ 55
Regulatory Assets: Current	52	52
Current Assets: Other	242	162
Other Noncurrent Assets: Regulatory assets	989	1,041
Other Noncurrent Assets: Other	110	261
Current maturities of long-term debt	216	227
Long-Term Debt	3,997	3,998
Other Noncurrent Liabilities: Other	$ 228	212
Series A Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.001
Preferred stock, depositary shares authorized	40,000,000
Preferred stock, depositary shares outstanding	40,000,000
Series B Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.001
Preferred stock, depositary shares authorized	1,000,000
Preferred stock, depositary shares outstanding	1,000,000
Duke Energy Carolinas
Allowance for doubtful accounts - receivables	$ 3	2
Regulatory Assets: Current	550	520
Current Assets: Other	21	72
Other Noncurrent Assets: Regulatory assets	3,360	3,457
Other Noncurrent Assets: Other	1,149	1,027
Current maturities of long-term debt	458	6
Long-Term Debt	11,142	10,633
Other Noncurrent Liabilities: Other	627	671
Duke Energy Carolinas | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	7	7
Progress Energy
Allowance for doubtful accounts - receivables	7	5
Regulatory Assets: Current	946	1,137
Current Assets: Other	210	125
Other Noncurrent Assets: Regulatory assets	6,346	6,564
Other Noncurrent Assets: Other	1,049	974
Current maturities of long-term debt	1,577	1,672
Long-Term Debt	17,907	17,089
Other Noncurrent Liabilities: Other	$ 383	$ 351
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100	100
Common stock, shares outstanding	100	100
Progress Energy | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	$ 9	$ 8
Regulatory Assets: Current	52	52
Current Assets: Other	39	39
Other Noncurrent Assets: Regulatory assets	989	1,041
Current maturities of long-term debt	54	53
Long-Term Debt	1,632	1,636
Duke Energy Progress
Allowance for doubtful accounts - receivables	3	2
Regulatory Assets: Current	526	703
Current Assets: Other	60	62
Other Noncurrent Assets: Regulatory assets	4,152	4,111
Other Noncurrent Assets: Other	651	612
Current maturities of long-term debt	1,006	603
Long-Term Debt	7,902	7,451
Other Noncurrent Liabilities: Other	92	106
Duke Energy Progress | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	5	5
Duke Energy Florida
Allowance for doubtful accounts - receivables	3	3
Regulatory Assets: Current	419	434
Current Assets: Other	58	46
Other Noncurrent Assets: Regulatory assets	2,194	2,454
Other Noncurrent Assets: Other	311	311
Current maturities of long-term debt	571	270
Long-Term Debt	7,416	7,051
Other Noncurrent Liabilities: Other	136	93
Duke Energy Florida | Variable Interest Entity [Member]
Allowance for doubtful accounts - receivables of VIEs	4	3
Regulatory Assets: Current	52	52
Current Assets: Other	39	39
Other Noncurrent Assets: Regulatory assets	989	1,041
Current maturities of long-term debt	54	53
Long-Term Debt	1,307	1,336
Duke Energy Ohio
Allowance for doubtful accounts - receivables	4	2
Regulatory Assets: Current	49	33
Current Assets: Other	21	24
Other Noncurrent Assets: Regulatory assets	549	531
Other Noncurrent Assets: Other	52	41
Current maturities of long-term debt		551
Long-Term Debt	2,594	1,589
Other Noncurrent Liabilities: Other	$ 94	$ 93
Common stock, par value	$ 8.50	$ 8.50
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares outstanding	90,000,000	90,000,000
Duke Energy Indiana
Allowance for doubtful accounts - receivables	$ 3	$ 2
Regulatory Assets: Current	90	175
Current Assets: Other	60	35
Other Noncurrent Assets: Regulatory assets	1,082	982
Other Noncurrent Assets: Other	234	194
Current maturities of long-term debt	503	63
Long-Term Debt	3,404	3,569
Other Noncurrent Liabilities: Other	18	16
Piedmont
Allowance for doubtful accounts - receivables	6	2
Regulatory Assets: Current	73	54
Current Assets: Other	28	19
Other Noncurrent Assets: Regulatory assets	290	303
Other Noncurrent Assets: Other	121	52
Current maturities of long-term debt		350
Long-Term Debt	2,384	1,788
Other Noncurrent Liabilities: Other	$ 148	$ 177
Common stock, shares authorized	100	100
Common stock, shares outstanding	100	100