Asset Retirement Obligations Narrative (Details) (USD $)					3 Months Ended
Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Arizona Public Service Company	Dec. 31, 2013 Arizona Public Service Company	Mar. 31, 2014 Arizona Public Service Company Four Corners Units 1-3	Jun. 30, 2014 Arizona Public Service Company Palo Verde
Asset Retirement Obligations
Amount of update on account of decommissioning study					$ 24,000,000	$ 20,000,000
Asset Retirement Obligation, Current	39,416,000	32,896,000	39,416,000	32,896,000
Asset Retirement Obligation Total	$ 390,000,000		$ 390,000,000	$ 347,000,000

Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Name:	us-gaap_AssetRetirementObligationCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant