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Asset Retirement Obligations (Details) - ARIZONA PUBLIC SERVICE COMPANY - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Asset Retirement Obligations |  |
Newly incurred or acquired obligations | $ 17,864 | $ 0
ARO, decrease | 1,000 |
Change in asset retirement obligations |  |
Asset retirement obligations at the beginning of year | 679,529 | 624,475
Changes attributable to: |  |
Accretion expense | 36,876 | 33,104
Settlements | (9,726) | 0
Estimated cash flow revisions | 2,002 | 21,950
Newly incurred or acquired obligations | 17,864 | 0
Asset retirement obligations at the end of year | 726,545 | 679,529
Solar Panels |  |
Asset Retirement Obligations |  |
Newly incurred or acquired obligations | 14,000 |
Changes attributable to: |  |
Newly incurred or acquired obligations | 14,000 |
4CA |  |
Asset Retirement Obligations |  |
ARO, decrease | 9,000 |
Navajo Generating Station |  |
Asset Retirement Obligations |  |
Newly incurred or acquired obligations |  | 22,000
Increase in regulatory asset |  | 2,000
Decrease in regulatory liability |  | 20,000
Changes attributable to: |  |
Newly incurred or acquired obligations |  | $ 22,000
Consumer Solar Panels |  |
Asset Retirement Obligations |  |
Newly incurred or acquired obligations | 7,000 |
Changes attributable to: |  |
Newly incurred or acquired obligations | $ 7,000 |

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- Definition Asset Retirement Obligation, Increase in Regulatory Asset + References No definition available. + Details
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- Definition Asset Retirement Obligation, Liabilities Incurred, Decrease in Regulatory Liability + References No definition available. + Details
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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://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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- Definition Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. + 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)(3) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 + Details
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- Definition Amount of asset retirement obligations incurred during the period. + 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)(1) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset. + 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)(2) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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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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- Definition Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 35 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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