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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 27, 2018 | Jan. 29, 2016 | Jun. 01, 2001 | Dec. 31, 2018 | Apr. 01, 2019 | Dec. 31, 2016
Loss Contingencies [Line Items] |  |  |  |  |  |
Nuclear insurance liability limit per incident |  |  |  | $ 14,070,000 |  |
Required nuclear liability insurance |  |  |  | 450,000 |  |
Nuclear financial protection pool mandated by the Price-Anderson Act |  |  |  | 13,400,000 |  |
Maximum assessment mandated by Price-Anderson Act per nuclear reactor for a nuclear incident |  |  |  | $ 138,000 |  |
Maximum assessment, administrative fee (as percent) |  |  |  | 5.00% |  |
Maximum annual assessment payment mandated by Price-Anderson Act for a nuclear incident |  |  |  | $ 21,000 |  |
44% maximum assessment |  |  |  | 44.00% |  |
Nuclear operator maximum annual assessment |  |  |  | $ 9,000 |  |
Maximum liability per nuclear incident |  |  |  | 61,000 |  |
Mutual property insurance additional blanket policy property coverage |  |  |  | 1,250,000 |  |
Nuclear property insurance coverage limit per individual insured |  |  |  | 1,500,000 |  |
Lost revenue insurance maximum weekly recovery |  |  |  | 3,000 |  |
Accidental outage weekly recovery limit for loss revenues from a nuclear industry mutual insurance company in the event of insurable loss |  |  |  | $ 1,980 |  |
Multiplier that the industry mutual insurance company may assess against insureds premium |  |  |  | 10 |  |
The number of months a nuclear industry mutual insurance company will respond to retrospective premium adjustments |  |  |  | 24 months |  |
Number of years board of directors of industry mutual insurance company can adjust policy after policy expires |  |  |  | 6 years |  |
Midwest Generation Asbestos Liabilities |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Damages sought | $ 61,000 |  |  |  |  |
CDWR and SDGE v Sunrise Power |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Power Purchase Agreement (PPA) period |  |  | 10 years |  |  |
Damages sought |  | $ 1,200 |  |  |  |
Remaining term |  | 70 months |  |  |  |
Nuclear Event |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Total nuclear property insurance coverage |  |  |  | $ 2,750,000 |  |
Lost revenue insurance maximum weekly recovery |  |  |  | 274,000 |  |
Accidental outage weekly recovery limit for loss revenues from a nuclear industry mutual insurance company in the event of insurable loss |  |  |  | 216,000 |  |
Non-nuclear Event |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Total nuclear property insurance coverage |  |  |  | 1,500,000 |  |
Lost revenue insurance maximum weekly recovery |  |  |  | 184,000 |  |
Accidental outage weekly recovery limit for loss revenues from a nuclear industry mutual insurance company in the event of insurable loss |  |  |  | $ 144,000 |  |
Non-nuclear Event | Scenario, Forecast |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Total nuclear property insurance coverage |  |  |  |  | $ 1,000,000 |
Lignite Contract with Texas Westmoreland Coal Co. |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Bond obligation |  |  |  |  |  | $ 99,000

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- Definition The industry mutual insurance company may assess the company: 10 times the amount of the total annual premium. + References No definition available. + Details
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- Definition Maximum assessment to be paid per nuclear reactor for a nuclear incident under the financial protection pool mandated by the Price-Anderson Act. This assessment is paid by each United State nuclear reactor operator over multiple years at a limited amount per year in the event of an incident at any US nuclear reactor. + References No definition available. + Details
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