Represents the number of non-financial separate performance metrics based on which the awards vest.

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The number of shares awarded to an employee for each unit award earned. The cash payment is calculated by multiplying the shares awarded by the fair market value of a share determined at a pre-established valuation date.

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Represents the percentage of the awards that vest based on non-financial separate performance metrics.

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Represents the percentage of the equity based awards that vest based on a percentile ranking of total shareholder return compared with the total shareholder return of all relevant companies in a specified utilities index.

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Represents the percentage of cash that the participant may elect as a deferred dividend equivalent payment under the first option available under the plan.

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No definition available.

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Represents the percentage of cash that the participant may elect as a deferred grant under the first option available under the plan.

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Represents the percentage of fully transferable shares of stock that the participant may elect as a deferred dividend equivalent payment for the first option available under the plan.

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No definition available.

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Represents the percentage of fully transferable shares of stock that the participant may elect as a deferred dividend equivalent payment for the second option available under the plan.

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No definition available.

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Represents the percentage of fully transferable shares of stock that the participant may elect as a deferred grant for the first option available under the plan.

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No definition available.

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Represents the percentage of fully transferable shares of stock that the participant may elect as a deferred grant for the second option available under the plan.

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No definition available.

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Represents the number of additional grants to be made during the period on other than stock (or unit) option plans if performance requirements are met.

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No definition available.

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Number of performance elements criteria that affect the number of shares received after the end of the specified performance period, if performance criteria conditions are met.

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No definition available.

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Represents the number of shares issued as a percentage of the target award.

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No definition available.

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- Definition

Percentage of awards that are no longer contingent on satisfaction of either a service condition, market condition or a performance condition on the first vesting year from the grant date, thereby giving the employee the legal right to convert the award to shares.

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No definition available.

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- Definition

Percentage of awards that are no longer contingent on satisfaction of either a service condition, market condition or a performance condition on the second vesting year from the grant date, thereby giving the employee the legal right to convert the award to shares.

+ References

No definition available.

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Percentage of awards that are no longer contingent on satisfaction of either a service condition, market condition or a performance condition on the third vesting year from the grant date, thereby giving the employee the legal right to convert the award to shares.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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-Name Accounting Standards Codification

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Stock-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended		1 Months Ended	0 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 15, 2014	Feb. 15, 2013	Dec. 31, 2012	Feb. 15, 2015	Mar. 31, 2014	May 16, 2012
Stock Options
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted	$ 15
Expected weighted-average period of recognition of unrecognized compensation cost	2 years
Total fair value of shares vested	20	20	19
Compensation cost that has been charged against income	33	25	32
Total income tax benefit recognized	13	10	13
2013 Grant
Stock-Based Compensation
Common shares to be available for grant under the 2012 Long Term Incentive Plan									4,595,500
Restricted stock unit awards
Restricted Stock Unit Awards and Stock Grants
Percentage of cash that the participant may elect as a dividend for the first option available under the plan	50.00%
Percentage of fully transferable shares of stock that the participant may elect as a deferral for the first option available under the plan	50.00%
Percentage of cash that the participant may elect as a dividend equivalent deferral under the first option available under the plan	50.00%
Percentage of fully transferable shares of stock that the participant may elect as a dividend equivalent deferral for the first option available under the plan	50.00%
Percentage of cash that the participant may elect as a dividend equivalent deferral under the first option available under the plan	50.00%
Percentage of fully transferable shares of stock that the participant may elect as a dividend equivalent deferral for the first option available under the plan	50.00%
Vesting period	4 years
Percentage of awards vesting on February 15, 2013					50.00%
Percentage of awards vesting on February 15, 2014				25.00%
Restricted stock units and stock grants
Restricted Stock Unit Awards and Stock Grants
Granted (in shares)	130,273
Performance Share Awards
Restricted Stock Unit Awards and Stock Grants
Granted (in shares)	166,244
Performance Share Awards \| 2013 Grant
Performance Shares
Performance period			3 years
Percentage of the awards that vest based on a percentile ranking of total shareholder return		50.00%
Percentage of the awards that vest based on non-financial separate performance metrics		50.00%
Number of non-financial separate performance metrics based on which awards vest		6
Performance Share Awards \| 2013 Grant \| Maximum
Performance Shares
Exact number of shares issued as a percentage of the target award			200.00%
Performance Share Awards \| 2013 Grant \| Minimum
Performance Shares
Exact number of shares issued as a percentage of the target award			0.00%
Performance Share Awards \| 2008 Grant
Performance Shares
Number of performance element criteria	2
Performance period	3 years
Performance Share Awards \| 2012 Grant
Performance Shares
Percentage of the awards that vest based on a percentile ranking of total shareholder return	50.00%
Percentage of the awards that vest based on non-financial separate performance metrics	50.00%
Number of non-financial separate performance metrics based on which awards vest	6
Performance Share Awards \| 2012 Grant \| Maximum
Performance Shares
Exact number of shares issued as a percentage of the target award		200.00%
Performance Share Awards \| 2012 Grant \| Minimum
Performance Shares
Exact number of shares issued as a percentage of the target award		0.00%
Performance Share Awards \| 2014 Grant
Performance Shares
Performance period		3 years
Percentage of the awards that vest based on a percentile ranking of total shareholder return			50.00%
Percentage of the awards that vest based on non-financial separate performance metrics			50.00%
Number of non-financial separate performance metrics based on which awards vest			6
Performance Share Awards \| 2014 Grant \| Maximum
Performance Shares
Exact number of shares issued as a percentage of the target award	200.00%
Performance Share Awards \| 2014 Grant \| Minimum
Performance Shares
Exact number of shares issued as a percentage of the target award	0.00%
Retention Units
Restricted Stock Unit Awards and Stock Grants
Granted (in shares)						50,617
Additional shares to be granted as retention award if performance requirements are met						33,745
ARIZONA PUBLIC SERVICE COMPANY
Stock Options
Compensation cost that has been charged against income	$ 33	$ 25	$ 32
Subsequent event \| Restricted stock unit awards
Restricted Stock Unit Awards and Stock Grants
Percentage of awards vesting on February 15, 2015							25.00%
Chief Executive Officer \| Restricted stock unit awards
Restricted Stock Unit Awards and Stock Grants
Number of shares of stock awarded for each unit	1
Officer \| Restricted stock unit awards
Restricted Stock Unit Awards and Stock Grants
Number of shares of stock awarded for each unit								1