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Income Taxes - Summary of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Tax [Line Items] |  |  |
Tax positions, that if recognized, would decrease our effective tax rate | $ 19,504 | $ 16,373 | $ 11,313
Unrecognized tax benefit interest expense/(benefit) recognized | (780) | 577 | 529
Unrecognized tax benefit interest accrued | 1,130 | 1,910 | 1,333
ARIZONA PUBLIC SERVICE COMPANY |  |  |
Income Tax [Line Items] |  |  |
Tax positions, that if recognized, would decrease our effective tax rate | 19,504 | 16,373 | 11,313
Unrecognized tax benefit interest expense/(benefit) recognized | (780) | 577 | 529
Unrecognized tax benefit interest accrued | $ 1,130 | $ 1,910 | $ 1,333

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- Definition [Line Items] for Income Tax [Table] + References No definition available. + Details
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- Definition Amount of interest expense accrued for an underpayment of income taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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- Definition Amount of interest expense for an underpayment of income taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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