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Regulatory Matters - Deferred Fuel and Purchased Power Regulatory Asset (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Change in regulatory asset |  |  |
Deferred fuel and purchased power costs — current period | $ 82,481 | $ 78,277 | $ 48,405
Amounts charged to customers | (49,508) | (116,750) | 14,767
ARIZONA PUBLIC SERVICE COMPANY |  |  |
Change in regulatory asset |  |  |
Deferred fuel and purchased power costs — current period | 82,481 | 78,277 | 48,405
Amounts charged to customers | (49,508) | (116,750) | 14,767
ACC | ARIZONA PUBLIC SERVICE COMPANY | Power Supply Adjustor (PSA) |  |  |
Change in regulatory asset |  |  |
Beginning balance | 37,164 | 75,637 |
Deferred fuel and purchased power costs — current period | 82,481 | 78,277 |
Amounts charged to customers | (49,508) | (116,750) |
Ending balance | $ 70,137 | $ 37,164 | $ 75,637

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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=118932676&loc=d3e3602-108585 + Details
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