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Commitments and Contingencies - Superfund-Related Matters, Southwest Power Outage and Clean Air Act (Details) - Arizona Public Service Company $ in Millions |  |  | 3 Months Ended
--- | --- | --- | ---
Aug. 06, 2013 Defendant | Sep. 08, 2011 kV Customer | Mar. 31, 2016 USD ($)
Loss Contingencies [Line Items] |  |  |
Capacity of transmission line that tripped out of service (in kV) | 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 |  |  |
Loss Contingencies [Line Items] |  |  |
Costs related to investigation and study under Superfund site | $ |  |  | $ 2
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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- Definition Represents the number of customers losing service after the generation and transmission resources were lost in the power outage. + References No definition available. + Details
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- Definition Represents the period, after the transmission line went off-line, until the generation and transmission resources were lost in the power outage. + References No definition available. + Details
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- Details
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- Details
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