Regulatory Matters Regulatory Matters - Retail Rate Case Filing (Details) - Retail Rate Case Filing with Arizona Corporation Commission - ACC - ARIZONA PUBLIC SERVICE COMPANY	Jun. 01, 2016
Proposed Capital Structure and Costs of Capital
Requested debt capital structure (as a percent)	44.20%
Requested debt cost of capital (as a percent)	5.13%
Requested equity capital structure (as a percent)	55.80%
Requested equity cost of capital (as a percent)	10.50%
Requested weighted-average cost of capital (as a percent)	8.13%

Public Utilities, Requested Debt Cost of Capital, Percentage

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Public Utilities, Requested Equity 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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