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Commitments and Contingencies - Superfund-Related Matters and Southwest Power Outage (Details) - ARIZONA PUBLIC SERVICE COMPANY $ in Millions |  |  | 12 Months Ended
--- | --- | --- | ---
Aug. 06, 2013 Defendant | Sep. 08, 2011 kV Customer | Dec. 31, 2016 USD ($)
Superfund |  |  |
Costs related to investigation and study under Superfund site | $ |  |  | $ 2
Southwest Power Outage |  |  |
Power outage capacity of transmission line that tripped out of service | kV |  | 500 |
Period, after the transmission line went off-line, over which generation and transmission resources for the Yuma area were lost |  | 10 minutes |
Number of customers losing service in Yuma area | Customer |  | 69,700 |
Contaminated groundwater wells |  |  |
Superfund |  |  |
Number of defendants against whom Roosevelt Irrigation District ("RID") filed lawsuit | Defendant | 24 |  |

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- Definition Costs related to site-wide groundwater remedial investigation and feasibility study work plan because subsidiary has been found to be potentially responsible parties ("PRPs") with liability for cleanup of hazardous substances that contaminates the soil, water or air, under the Comprehensive Environmental Response, Compensation and Liability Act ("Superfund"). + References No definition available. + Details
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- Definition Power Outage Capacity of Transmission Line that Tripped out of Service + References No definition available. + Details
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- Details
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