Represent information pertaining to share of the assessment.

No definition available.

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Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represent information pertaining to total amount of coal severance surtax, penalty, and interest related to coal supplied under the coal supply agreement.

+ References

No definition available.

+ Details

Name:	pnw_LossContingencyCoalSeveranceSurtaxPenaltyAndInterest
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the percentage of share of the cost of control acquired by the entity.

+ References

No definition available.

+ Details

Name:	pnw_PercentageOfShareOfCostOfControl
Namespace Prefix:	pnw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_SiteContingencyLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 10

-Subparagraph (c),(d)(2)

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859

+ Details

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Period Type:	duration

Commitments and Contingencies (Details 3) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
	May 23, 2013 Four Corners New Mexico Tax Matter	Dec. 31, 2013 Four Corners ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2013 Four Corners ARIZONA PUBLIC SERVICE COMPANY New Mexico Tax Matter	Dec. 31, 2013 Navajo Plant ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2013 Cholla ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2013 Cholla Units 1-3 ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters
Expected environmental cost		$ 350		$ 200	$ 200	$ 120
Share of Cost of Control of Four Corners Units 4 and 5		63.00%
Coal severance surtax, penalty, and interest	30
Share of the assessment			$ 12