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Asset Retirement Obligations - Narrative (Details) - APS $ in Millions | 3 Months Ended
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Mar. 31, 2020 USD ($)
Four Corners |
Asset Retirement Obligations |
Asset retirement obligation, period increase (decrease) | $ (11)
Navajo Generating Station |
Asset Retirement Obligations |
Asset retirement obligation, period increase (decrease) | $ 5

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- Definition Amount of increase (decrease) in asset retirement obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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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