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v3.19.3.a.u2

Commitments and Contingencies (Narrative) (Details) $ in Millions |  |  |  | 2 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 11, 2020 claim | Jun. 18, 2018 USD ($) | Apr. 26, 2017 claim | Feb. 28, 2019 USD ($) | Dec. 31, 2019 USD ($) plant basin reactor claim | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) plant basin reactor claim | Jun. 13, 2019 claim | Dec. 31, 2018 USD ($) | May 16, 2017 claim
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 98 |  | 98 |  |  |
Insured public liability limit per nuclear incident |  |  |  |  | $ 13,900.0 |  | $ 13,900.0 |  |  |
Excess nuclear liability program coverage |  |  |  |  | 13,500.0 |  | 13,500.0 |  |  |
Pro rata assessment for each reactor owned for each incident exceeding public liability insurance |  |  |  |  | 138.0 |  | 138.0 |  |  |
Annual payment limit to pro rata assessments |  |  |  |  | 20.5 |  | 20.5 |  |  |
Industry aggregate limit |  |  |  |  | 3,200.0 |  | 3,200.0 |  |  |
Sublimit for non-nuclear terrorist events |  |  |  |  | 1,800.0 |  | 1,800.0 |  |  |
Sublimit property damage losses |  |  |  |  | 1,500.0 |  | 1,500.0 |  |  |
Additional nuclear accident limit |  |  |  |  | $ 1,250.0 |  | $ 1,250.0 |  |  |
Insurance coverage percentage initial weeks |  |  |  |  | 100.00% |  | 100.00% |  |  |
Accidental outage insurance coverage initial weeks |  |  |  |  |  |  | 365 days |  |  |
Insurance coverage percentage additional weeks |  |  |  |  | 80.00% |  | 80.00% |  |  |
Accidental outage insurance coverage additional weeks |  |  |  |  |  |  | 770 days |  |  |
Weeks of sublimits for accidental outage coverage |  |  |  |  |  |  | 728 days |  |  |
Sublimit accidental outage recovery |  |  |  |  | $ 328.0 |  | $ 328.0 |  |  |
Maximum magnitude of retroactive premiums |  |  |  |  | 10 |  | 10 |  |  |
Maximum period for retroactive premium assessment |  |  |  |  |  |  | 6 years |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reduction of prior year impairment |  |  |  |  | $ (14.0) | $ 25.0 | $ 11.0 |  |  |
Reserves for legal matters |  |  |  |  | $ 62.0 |  | $ 62.0 |  | $ 65.0 |
Coal Ash Insurance Coverage Litigation |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Number of NC and SC plants with ash basins | plant |  |  |  |  | 15 |  | 15 |  |  |
NCDEQ State Enforcement Actions |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Number of Plants with No Disputed Facts | plant |  |  |  |  | 7 |  | 7 |  |  |
Facilities with ash basins | plant |  |  |  |  | 14 |  | 14 |  |  |
Number of Plants with Disputed Facts | plant |  |  |  |  | 7 |  | 7 |  |  |
Duke Energy Carolinas |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Primary nuclear liability program coverage |  |  |  |  | $ 450.0 |  | $ 450.0 |  |  |
Max retroactive premium assessments |  |  |  |  |  |  | 155.0 |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reserves for legal matters |  |  |  |  | 2.0 |  | 2.0 |  | 9.0 |
Duke Energy Carolinas | Asbestos Issue |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Asbestos-related injuries and damages reserves |  |  |  |  | 604.0 |  | 604.0 |  | 630.0 |
Reinsurance retention policy, excess retention, amount reinsured |  |  |  |  |  |  | 747.0 |  |  |
Loss contingency, receivable, noncurrent |  |  |  |  | $ 742.0 |  | $ 742.0 |  | 739.0 |
Duke Energy Carolinas | Asbestos Issue | Non Malignant Asbestos Claim |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Loss contingency, pending claims, number | claim |  |  |  |  | 123 |  | 123 |  |  |
Asbestos-related injuries and damages reserves |  |  |  |  | $ 32.0 |  | $ 32.0 |  |  |
Duke Energy Carolinas | Asbestos Issue | Malignant Asbestos Claim |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Loss contingency, pending claims, number | claim |  |  |  |  | 49 |  | 49 |  |  |
Asbestos-related injuries and damages reserves |  |  |  |  | $ 16.0 |  | $ 16.0 |  |  |
Duke Energy Carolinas | McGuire |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 2 |  | 2 |  |  |
Accidental outage insurance coverage policy limit |  |  |  |  | $ 490.0 |  | $ 490.0 |  |  |
Duke Energy Carolinas | Catawba |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 2,000,000 |  | 2,000,000 |  |  |
Dedicated additional nuclear accident limit |  |  |  |  | $ 1,250.0 |  | $ 1,250.0 |  |  |
Additional Non-nuclear accident limit |  |  |  |  | 750.0 |  | 750.0 |  |  |
Accidental outage insurance coverage policy limit |  |  |  |  | $ 490.0 |  | $ 490.0 |  |  |
Potential obligation percentage |  |  |  |  | 100.00% |  | 100.00% |  |  |
Duke Energy Carolinas | Oconee |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 3 |  | 3 |  |  |
Additional Non-nuclear accident limit |  |  |  |  | $ 750.0 |  | $ 750.0 |  |  |
Accidental outage insurance coverage policy limit |  |  |  |  | $ 406.0 |  | $ 406.0 |  |  |
Duke Energy Carolinas and Duke Energy Progress |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 9 |  | 9 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 7 |  | 7 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Allen | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 2 |  | 2 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Belews Creek | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 1 |  | 1 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Mayo | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 1 |  | 1 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Roxboro | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 1 |  | 1 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Rogers | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 2 |  | 2 |  |  |
Duke Energy Carolinas and Duke Energy Progress | Marshall and Roxboro | Settled agreement |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of coal ash basins | basin |  |  |  |  | 2 |  | 2 |  |  |
Duke Energy Florida |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Primary nuclear liability program coverage |  |  |  |  | $ 100.0 |  | $ 100.0 |  |  |
Max retroactive premium assessments |  |  |  |  |  |  | 1.0 |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reserves for legal matters |  |  |  |  | 22.0 |  | 22.0 |  | 24.0 |
Duke Energy Florida | Spent Nuclear Fuel Matters |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Damages sought |  | $ 203.0 |  |  |  |  |  |  |  |
Duke Energy Florida | Fluor Letter Of Credit |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Drawings on credit facility |  |  |  | $ 67.0 |  |  |  |  |  |
Duke Energy Florida | Crystal River Unit 3 |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Sublimit property damage losses |  |  |  |  | 50.0 |  | 50.0 |  |  |
Duke Energy Florida | Citrus County Combined Cycle Facility |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reduction of prior year impairment |  |  |  |  |  |  | 36.0 |  |  |
Progress Energy |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reduction of prior year impairment |  |  |  |  | 11.0 | $ 25.0 | 36.0 |  |  |
Reserves for legal matters |  |  |  |  | 55.0 |  | 55.0 |  | 54.0 |
Duke Energy Progress |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Primary nuclear liability program coverage |  |  |  |  | 450.0 |  | 450.0 |  |  |
Max retroactive premium assessments |  |  |  |  |  |  | 94.0 |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reserves for legal matters |  |  |  |  | $ 12.0 |  | $ 12.0 |  | 12.0 |
Duke Energy Progress | RRBA Federal Citizens Suits |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Loss contingency, pending claims, number | claim |  |  |  |  |  |  |  |  |  | 1
Duke Energy Progress | Spent Nuclear Fuel Matters |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Damages sought |  | $ 100.0 |  |  |  |  |  |  |  |
Duke Energy Progress | Subsequent Event | RRBA Federal Citizens Suits |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Loss Contingency, Claims Dismissed, Number | claim | 3 |  |  |  |  |  |  |  |  |
Duke Energy Progress | Robinson |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 1 |  | 1 |  |  |
Accidental outage insurance coverage policy limit |  |  |  |  | $ 364.0 |  | $ 364.0 |  |  |
Duke Energy Progress | Harris |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 1,000,000 |  | 1,000,000 |  |  |
Accidental outage insurance coverage policy limit |  |  |  |  | $ 462.0 |  | $ 462.0 |  |  |
Duke Energy Progress | Brunswick |  |  |  |  |  |  |  |  |  |
Insurance [Abstract] |  |  |  |  |  |  |  |  |  |
Number of licensed nuclear reactors | reactor |  |  |  |  | 2 |  | 2 |  |  |
Accidental outage insurance coverage policy limit |  |  |  |  | $ 462.0 |  | $ 462.0 |  |  |
Duke Energy Progress | Mayo | RRBA Federal Citizens Suits |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Loss Contingency, Claims Dismissed, Number | claim |  |  | 4 |  |  |  |  |  |  |
Loss contingency, pending claims, number | claim |  |  |  |  |  |  |  |  |  | 2
Duke Energy Progress | Roxboro | RRBA Federal Citizens Suits |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Loss contingency, pending claims, number | claim |  |  |  |  |  |  |  | 2 |  |
Piedmont |  |  |  |  |  |  |  |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |  |  |  |  |  |  |  |
Reserves for legal matters |  |  |  |  | $ 1.0 |  | $ 1.0 |  | $ 1.0 |

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