Represent information pertaining to share of the assessment.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- 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

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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

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

- Details

Name:	us-gaap_SiteContingencyLineItems
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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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Commitments and Contingencies (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended	0 Months Ended	3 Months Ended
	Mar. 31, 2014 ARIZONA PUBLIC SERVICE COMPANY Four Corners Units 4 and 5	May 23, 2013 Four Corners New Mexico Tax Matter	Mar. 31, 2014 Four Corners ARIZONA PUBLIC SERVICE COMPANY New Mexico Tax Matter	Mar. 31, 2014 Navajo Plant ARIZONA PUBLIC SERVICE COMPANY	Mar. 31, 2014 Cholla ARIZONA PUBLIC SERVICE COMPANY	Mar. 31, 2014 Cholla Units 2 And 3 ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters
Expected environmental cost	$ 350			$ 200	$ 200	$ 130
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