Derivatives and Hedging (Notional Amounts of Derivative Instruments) (Details) Mcf in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022 USD ($) GWh Mcf	Dec. 31, 2021 USD ($) GWh Mcf
Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 3,490	$ 3,592
Commodity contracts | Cash flow hedges
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	9,763	9,975
Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	16,176	22,344
Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	860	823
Designated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 2,913	$ 2,415
Designated contracts | Interest Rate Contracts | VIE primary beneficiary
Derivative [Line Items]
Notional amount	663	665
Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	577	1,177
Duke Energy Carolinas | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 250	$ 350
Duke Energy Carolinas | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	284	264
Duke Energy Carolinas | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 250	$ 350
Progress Energy | Interest Rate Contracts
Derivative [Line Items]
Notional amount		$ 500
Progress Energy | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	243	215
Progress Energy | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount		$ 500
Duke Energy Progress | Interest Rate Contracts
Derivative [Line Items]
Notional amount		$ 500
Duke Energy Progress | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	243	215
Duke Energy Progress | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount		$ 500
Duke Energy Indiana | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 300	$ 300
Duke Energy Indiana | Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	4,501	10,688
Duke Energy Indiana | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	7	8
Duke Energy Indiana | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 300	$ 300
Duke Energy Ohio | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 27	$ 27
Duke Energy Ohio | Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	791	1,681
Duke Energy Ohio | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 27	$ 27
Piedmont | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	326	336