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Regulatory Matters - Deferred Fuel and Purchased Power Regulatory Asset (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Change in regulatory asset |  |  |
Deferred fuel and purchased power | $ 78,277 | $ 48,405 | $ 60,303
Deferred fuel and purchased power amortization | (116,750) | 14,767 | (38,152)
ARIZONA PUBLIC SERVICE COMPANY |  |  |
Change in regulatory asset |  |  |
Deferred fuel and purchased power | 78,277 | 48,405 | 60,303
Deferred fuel and purchased power amortization | (116,750) | 14,767 | (38,152)
ACC | ARIZONA PUBLIC SERVICE COMPANY | Power Supply Adjustor (PSA) |  |  |
Change in regulatory asset |  |  |
Beginning balance | 75,637 | 12,465 |
Deferred fuel and purchased power | 78,277 | 48,405 |
Deferred fuel and purchased power amortization | (116,750) | 14,767 |
Ending balance | $ 37,164 | $ 75,637 | $ 12,465

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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