Revenue (Aging of Trade Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Unbilled receivables	$ 964	$ 969
Not past due	2,104	1,789
Deferred Payment Arrangements	115	215
Trade and Other Receivables	3,732	3,299
30-60 days
Financing Receivable, Past Due [Line Items]
Past due	212	185
60-90 days
Financing Receivable, Past Due [Line Items]
Past due	88	22
90+ days
Financing Receivable, Past Due [Line Items]
Past due	249	119
Duke Energy Carolinas
Financing Receivable, Past Due [Line Items]
Unbilled receivables	316	328
Not past due	595	445
Deferred Payment Arrangements	55	96
Trade and Other Receivables	1,186	966
Duke Energy Carolinas | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	77	80
Duke Energy Carolinas | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	37	1
Duke Energy Carolinas | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	106	16
Progress Energy
Financing Receivable, Past Due [Line Items]
Unbilled receivables	266	283
Not past due	800	707
Deferred Payment Arrangements	45	80
Trade and Other Receivables	1,289	1,166
Progress Energy | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	72	54
Progress Energy | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	41	10
Progress Energy | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	65	32
Duke Energy Progress
Financing Receivable, Past Due [Line Items]
Unbilled receivables	193	167
Not past due	405	398
Deferred Payment Arrangements	22	52
Trade and Other Receivables	722	655
Duke Energy Progress | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	44	25
Duke Energy Progress | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	21	4
Duke Energy Progress | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	37	9
Duke Energy Florida
Financing Receivable, Past Due [Line Items]
Unbilled receivables	73	116
Not past due	393	307
Deferred Payment Arrangements	23	28
Trade and Other Receivables	565	509
Duke Energy Florida | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	28	29
Duke Energy Florida | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	20	6
Duke Energy Florida | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	28	23
Duke Energy Ohio
Financing Receivable, Past Due [Line Items]
Unbilled receivables	4	2
Not past due	42	60
Deferred Payment Arrangements	2
Trade and Other Receivables	100	102
Duke Energy Ohio | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	4	8
Duke Energy Ohio | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	1	2
Duke Energy Ohio | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	47	30
Duke Energy Indiana
Financing Receivable, Past Due [Line Items]
Unbilled receivables	27	16
Not past due	51	26
Trade and Other Receivables	103	58
Duke Energy Indiana | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	13	3
Duke Energy Indiana | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	1	1
Duke Energy Indiana | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	11	12
Piedmont
Financing Receivable, Past Due [Line Items]
Unbilled receivables	106	86
Not past due	202	149
Deferred Payment Arrangements	4	7
Trade and Other Receivables	333	262
Piedmont | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	12	8
Piedmont | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	2	3
Piedmont | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	$ 7	$ 9