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Asset Retirement Obligations - Narrative (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2016 USD ($) | Sep. 30, 2016 USD ($) turbine_unit | Dec. 31, 2015 USD ($)
Asset Retirement Obligations |  |  |
Asset retirement obligation, current | $ 11,852 | $ 11,852 | $ 28,573
Arizona Public Service Company |  |  |
Asset Retirement Obligations |  |  |
Newly incurred liabilities | 9,000 | 18,927 |
Asset retirement obligation, current | 11,505 | 11,505 | 28,573
Asset retirement obligation | $ 470,480 | $ 470,480 | $ 443,576
Arizona Public Service Company | Ocotillo Steam Units |  |  |
Asset Retirement Obligations |  |  |
Number of constructed turbine units | turbine_unit |  | 5 |
Newly incurred liabilities |  | $ 10,000 |

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- Definition 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. + References 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Asset Retirement Obligation -URI http://asc.fasb.org/extlink&oid=6505190 + Details
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- Definition 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. + References 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 + Details
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