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Regulatory Matters Regulatory Matters - Deferred Fuel and Purchased Power Regulatory Asset (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Change in regulatory asset |  |  |
Deferred fuel and purchased power | $ (60,303) | $ 14,997 | $ (26,927)
Deferred fuel and purchased power amortization | 38,152 | 1,617 | 40,757
ARIZONA PUBLIC SERVICE COMPANY |  |  |
Change in regulatory asset |  |  |
Deferred fuel and purchased power | (60,303) | 14,997 | (26,927)
Deferred fuel and purchased power amortization | 38,152 | 1,617 | 40,757
ACC | ARIZONA PUBLIC SERVICE COMPANY | Power Supply Adjustor (PSA) | Cost Recovery Mechanisms |  |  |
Change in regulatory asset |  |  |
Beginning balance | (9,688) | 6,926 |
Deferred fuel and purchased power | 60,303 | (14,997) |
Deferred fuel and purchased power amortization | (38,150) | (1,617) |
Ending balance | $ 12,465 | $ (9,688) | $ 6,926

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- Definition Deferred Fuel and Purchased Power Regulatory Asset (Liability), Current + References No definition available. + Details
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- Definition The amortization of deferred fuel and purchased power costs. + References No definition available. + Details
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- Definition The increase (decrease) during the reporting period in unrecovered fuel costs for a regulated utility company. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 + Details
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