Regulatory Matters - Capital Structure and Costs of Capital (Details)	Oct. 31, 2019
Cost of Capital
Long-term debt	4.10%
Common stock equity	10.15%
Weighted-average cost of capital	7.41%
Retail Rate Case Filing with Arizona Corporation Commission \| Arizona Public Service Company
Capital Structure
Common stock equity	54.70%
Retail Rate Case Filing with Arizona Corporation Commission \| ACC \| Arizona Public Service Company
Capital Structure
Long-term debt	45.30%

Capital Structure [Abstract]

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Cost Of Capital [Abstract]

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Public Utilities, Requested Equity Cost Of Capital, Percentage

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Public Utilities, Requested Long-term Debt Cost Of Capital, Percentage

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Public Utilities, Requested Weighted Average Cost Of Capital, Percentage

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Percentage of public utility's requested debt to capital, including debt and equity.

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Percentage of public utility's requested equity to capital, including debt and equity.

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