Leases (Finance Lease Maturities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Finance Lease, Liability, Payment, Due
2021	$ 186
2022	173
2023	174
2024	119
2025	51
Thereafter	762
Total finance lease payments	1,465
Less: amounts representing interest	(620)
Total finance lease liabilities	845	$ 969
Duke Energy Carolinas
Finance Lease, Liability, Payment, Due
2021	38
2022	38
2023	38
2024	38
2025	38
Thereafter	502
Total finance lease payments	692
Less: amounts representing interest	(398)
Total finance lease liabilities	294	179
Progress Energy
Finance Lease, Liability, Payment, Due
2021	68
2022	68
2023	68
2024	52
2025	48
Thereafter	481
Total finance lease payments	785
Less: amounts representing interest	(408)
Total finance lease liabilities	377	405
Duke Energy Progress
Finance Lease, Liability, Payment, Due
2021	43
2022	43
2023	43
2024	43
2025	43
Thereafter	475
Total finance lease payments	690
Less: amounts representing interest	(394)
Total finance lease liabilities	296	307
Duke Energy Florida
Finance Lease, Liability, Payment, Due
2021	25
2022	25
2023	25
2024	9
2025	5
Thereafter	6
Total finance lease payments	95
Less: amounts representing interest	(14)
Total finance lease liabilities	81	98
Duke Energy Indiana
Finance Lease, Liability, Payment, Due
2021	1
2022	1
2023	1
2024	1
2025	1
Thereafter	26
Total finance lease payments	31
Less: amounts representing interest	(21)
Total finance lease liabilities	$ 10	$ 10

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