$PNW
PINNACLE WEST CAPITAL CORP Stock $pnw

$pnw Overview Financials Valuation SEC Filings Company Website

2018 Form 10-K Financial Statement

#000076462219000019 Filed on February 22, 2019

Income Statement

Concept	2018	2017 Q4	2017 Q3
Revenue	$3.691B	$759.7M	$1.183B
YoY Change	3.53%	2.77%	1.41%
Cost Of Revenue	$1.076B		$310.5M
YoY Change	9.66%		-7.63%
Gross Profit	$2.615B		$872.9M
YoY Change	1.2%		5.06%
Gross Profit Margin	70.85%		73.76%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$651.0M	$164.9M	$154.4M
YoY Change	6.6%	16.05%	9.82%
% of Gross Profit	24.89%		17.69%
Operating Expenses	$2.931B	$650.3M	$717.7M
YoY Change	14.14%	0.46%	5.45%
Operating Profit	$773.7M	$85.55M	$459.5M
YoY Change	-14.96%	-30.35%	1.84%
Interest Expense	$218.3M	-$61.70M	$49.64M
YoY Change	10.42%	1662.86%	5.69%
% of Operating Profit	28.21%	-72.12%	10.8%
Other Income/Expense, Net	$109.0M	-$400.0K	$15.36M
YoY Change	101.4%	-86.67%	203.56%
Pretax Income	$664.4M	$47.30M	$425.3M
YoY Change	-13.29%	-44.61%	3.89%
Income Tax	$133.9M	$20.78M	$144.3M
% Of Pretax Income	20.15%	43.92%	33.94%
Net Earnings	$530.5M	$26.50M	$280.9M
YoY Change	4.45%	-54.4%	4.87%
Net Earnings / Revenue	14.37%	3.49%	23.74%
Basic Earnings Per Share	$4.56	$0.19	$2.47
Diluted Earnings Per Share	$4.54	$0.19	$2.46
COMMON SHARES
Basic Shares Outstanding	112.1M shares	111.7M shares	111.8M shares
Diluted Shares Outstanding	112.6M shares		112.4M shares

Balance Sheet

Concept	2018	2017 Q4	2017 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$6.000M	$14.00M	$11.00M
YoY Change	-57.14%	55.56%	-77.08%
Cash & Equivalents	$6.000M	$13.89M	$10.67M
Short-Term Investments
Other Short-Term Assets	$361.0M	$48.04M	$45.91M
YoY Change	-11.95%	6.69%	6.06%
Inventory	$294.0M	$289.0M	$284.0M
Prepaid Expenses
Receivables	$264.0M	$303.0M	$423.0M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$925.0M	$1.016B	$1.174B
YoY Change	-8.96%	23.6%	20.12%
LONG-TERM ASSETS
Property, Plant & Equipment	$13.77B	$11.67B	$11.27B
YoY Change	4.39%	2.62%	2.65%
Goodwill
YoY Change
Intangibles		$257.2M	$256.2M
YoY Change		185.7%	164.7%
Long-Term Investments
YoY Change
Other Assets	$2.710B	$52.04M	$88.82M
YoY Change	5.94%	-24.65%	28.76%
Total Long-Term Assets	$16.74B	$16.00B	$15.80B
YoY Change	4.6%	5.41%	6.58%
TOTAL ASSETS
Total Short-Term Assets	$925.0M	$1.016B	$1.174B
Total Long-Term Assets	$16.74B	$16.00B	$15.80B
Total Assets	$17.66B	$17.02B	$16.98B
YoY Change	3.79%	6.34%	7.42%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$277.0M	$256.4M	$236.7M
YoY Change	8.2%	-3.09%	-4.59%
Accrued Expenses	$61.00M	$56.00M	$49.00M
YoY Change	8.93%	5.66%	6.52%
Deferred Revenue		$70.39M
YoY Change
Short-Term Debt	$76.00M	$95.40M	$131.4M
YoY Change	-20.0%	-46.16%	12.02%
Long-Term Debt Due	$500.0M	$82.00M	$207.0M
YoY Change	509.76%	-34.4%	1117.65%
Total Short-Term Liabilities	$1.649B	$1.198B	$1.303B
YoY Change	37.65%	-7.35%	17.43%
LONG-TERM LIABILITIES
Long-Term Debt	$4.638B	$4.790B	$4.491B
YoY Change	-3.17%	19.09%	8.34%
Other Long-Term Liabilities	$4.020B	$148.9M	$158.4M
YoY Change	0.53%	-5.02%	-16.77%
Total Long-Term Liabilities	$8.658B	$4.939B	$4.649B
YoY Change	-1.49%	18.19%	7.24%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.649B	$1.198B	$1.303B
Total Long-Term Liabilities	$8.658B	$4.939B	$4.649B
Total Liabilities	$12.44B	$6.136B	$5.953B
YoY Change	3.57%	12.15%	9.31%
SHAREHOLDERS EQUITY
Retained Earnings		$2.443B	$2.576B
YoY Change		8.29%	9.97%
Common Stock		$2.615B	$2.609B
YoY Change		0.72%	2.19%
Preferred Stock
YoY Change
Treasury Stock (at cost)		$5.624M	$833.0K
YoY Change		36.08%	540.77%
Treasury Stock Shares		64.46K shares	9.864K shares
Shareholders Equity	$5.223B	$5.007B	$5.142B
YoY Change
Total Liabilities & Shareholders Equity	$17.66B	$17.02B	$16.98B
YoY Change	3.79%	6.34%	7.42%

Cashflow Statement

Concept	2018	2017 Q4	2017 Q3
OPERATING ACTIVITIES
Net Income	$530.5M	$26.50M	$280.9M
YoY Change	4.45%	-54.4%	4.87%
Depreciation, Depletion And Amortization	$651.0M	$164.9M	$154.4M
YoY Change	6.6%	16.05%	9.82%
Cash From Operating Activities	$1.277B	$346.1M	$481.3M
YoY Change	14.23%	33.99%	40.48%
INVESTING ACTIVITIES
Capital Expenditures	-$1.178B	-$381.0M	-$334.2M
YoY Change	-16.37%	46.2%	17.97%
Acquisitions
YoY Change
Other Investing Activities	-$1.941M	-$7.900M	-$17.30M
YoY Change	-110.17%	-141.58%	46.61%
Cash From Investing Activities	-$1.193B	-$388.9M	-$351.4M
YoY Change	-16.5%	60.97%	19.12%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net	-$5.055M
YoY Change	-62.25%
Debt Paid & Issued, Net	$182.0M
YoY Change	45.6%
Cash From Financing Activities	-$92.45M	46.00M	-124.3M
YoY Change	-129.3%	-182.0%	193.85%
NET CHANGE
Cash From Operating Activities	$1.277B	346.1M	481.3M
Cash From Investing Activities	-$1.193B	-388.9M	-351.4M
Cash From Financing Activities	-$92.45M	46.00M	-124.3M
Net Change In Cash	-$8.126M	3.200M	5.600M
YoY Change	-262.16%	-108.12%	5.66%
FREE CASH FLOW
Cash From Operating Activities	$1.277B	$346.1M	$481.3M
Capital Expenditures	-$1.178B	-$381.0M	-$334.2M
Free Cash Flow	$2.455B	$727.1M	$815.5M
YoY Change	-2.83%	40.12%	30.29%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2018	dei	Amendment Flag AmendmentFlag	false
CY2018	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2018	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2018	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2018
CY2018	dei	Document Period End Date DocumentPeriodEndDate	2018-12-31
CY2018	dei	Entity Central Index Key EntityCentralIndexKey	0000764622
CY2019Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	112146511	shares
CY2018	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2018	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2018	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2018Q2	dei	Entity Public Float EntityPublicFloat	9020511769.84	USD
CY2018	dei	Entity Shell Company EntityShellCompany	false
CY2018	dei	Entity Small Business EntitySmallBusiness	false
CY2018	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2018	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2017Q4	pnw	Accumulated Amortization On Nuclear Fuel AccumulatedAmortizationOnNuclearFuel	144070000	USD
CY2018Q4	pnw	Accumulated Amortization On Nuclear Fuel AccumulatedAmortizationOnNuclearFuel	137850000	USD
CY2016	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.56
CY2017	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.70
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.87
CY2017Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2018Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2017Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	150000000	shares
CY2018Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	150000000	shares
CY2017Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	111816170	shares
CY2018Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	112159896	shares
CY2017Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	582272000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	591202000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	633000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	693000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-1585000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-985000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-1294000	USD
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CY2016	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	585000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-24000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	78000	USD
CY2017Q4	us-gaap	Sale Leaseback Transaction Accumulated Depreciation SaleLeasebackTransactionAccumulatedDepreciation	241405000	USD
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CY2017Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	64463	shares
CY2018Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	58135	shares
CY2018	dei	Document Type DocumentType	10-K
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CY2018Q4	us-gaap	Derivative Instruments And Hedges DerivativeInstrumentsAndHedges	1113000	USD
CY2017Q4	us-gaap	Derivative Instruments And Hedges DerivativeInstrumentsAndHedges	1931000	USD
CY2018Q4	pnw	Deferred Fuel And Purchased Power Regulatory Asset Current DeferredFuelAndPurchasedPowerRegulatoryAssetCurrent	37164000	USD
CY2017Q4	pnw	Deferred Fuel And Purchased Power Regulatory Asset Current DeferredFuelAndPurchasedPowerRegulatoryAssetCurrent	75637000	USD
CY2018Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	129738000	USD
CY2017Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	172451000	USD
CY2018Q4	us-gaap	Other Assets Current OtherAssetsCurrent	56128000	USD
CY2017Q4	us-gaap	Other Assets Current OtherAssetsCurrent	48039000	USD
CY2018Q4	us-gaap	Assets Current AssetsCurrent	924991000	USD
CY2017Q4	us-gaap	Assets Current AssetsCurrent	1016288000	USD
CY2018Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	851134000	USD
CY2017Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	871000000	USD
CY2018Q4	pnw	Coal Reclamationand Union Trust CoalReclamationandUnionTrust	236101000	USD
CY2017Q4	pnw	Coal Reclamationand Union Trust CoalReclamationandUnionTrust	32542000	USD
CY2018Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	103247000	USD
CY2017Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	52040000	USD
CY2018Q4	pnw	Total Investments And Other Assets TotalInvestmentsAndOtherAssets	1190482000	USD
CY2017Q4	pnw	Total Investments And Other Assets TotalInvestmentsAndOtherAssets	955582000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	18736628000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	17798061000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	6366014000	USD
CY2017Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	6128535000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	12370614000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	11669526000	USD
CY2018Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	1170062000	USD
CY2017Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	1291498000	USD
CY2018Q4	us-gaap	Variable Interest Entity Consolidated Carrying Amount Assets VariableInterestEntityConsolidatedCarryingAmountAssets	105775000	USD
CY2017Q4	us-gaap	Variable Interest Entity Consolidated Carrying Amount Assets VariableInterestEntityConsolidatedCarryingAmountAssets	109645000	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	262902000	USD
CY2017Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	257189000	USD
CY2018Q4	us-gaap	Nuclear Fuel Net Of Amortization NuclearFuelNetOfAmortization	120217000	USD
CY2017Q4	us-gaap	Nuclear Fuel Net Of Amortization NuclearFuelNetOfAmortization	117408000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	14029570000	USD
CY2017Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	13445266000	USD
CY2018Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1342941000	USD
CY2017Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1202302000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	46906000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	268978000	USD
CY2018Q4	us-gaap	Other Deferred Costs Net OtherDeferredCostsNet	129312000	USD
CY2017Q4	us-gaap	Other Deferred Costs Net OtherDeferredCostsNet	130666000	USD
CY2018Q4	pnw	Total Deferred Debits TotalDeferredDebits	1519159000	USD
CY2017Q4	pnw	Total Deferred Debits TotalDeferredDebits	1601946000	USD
CY2018Q4	us-gaap	Assets Assets	17664202000	USD
CY2017Q4	us-gaap	Assets Assets	17019082000	USD
CY2018Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	277336000	USD
CY2017Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	256442000	USD
CY2018Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	154819000	USD
CY2017Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	148946000	USD
CY2018Q4	us-gaap	Interest Payable Current InterestPayableCurrent	61107000	USD
CY2017Q4	us-gaap	Interest Payable Current InterestPayableCurrent	56397000	USD
CY2018Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	82675000	USD
CY2017Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	77667000	USD
CY2018Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	76400000	USD
CY2017Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	95400000	USD
CY2018Q4	us-gaap	Other Long Term Debt Current OtherLongTermDebtCurrent	500000000	USD
CY2017Q4	us-gaap	Other Long Term Debt Current OtherLongTermDebtCurrent	82000000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	91174000	USD
CY2017Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	70388000	USD
CY2018Q4	us-gaap	Derivative Instruments And Hedges Liabilities DerivativeInstrumentsAndHedgesLiabilities	35506000	USD
CY2017Q4	us-gaap	Derivative Instruments And Hedges Liabilities DerivativeInstrumentsAndHedgesLiabilities	59252000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	19842000	USD
CY2017Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	4745000	USD
CY2018Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	165876000	USD
CY2017Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	100086000	USD
CY2018Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	184229000	USD
CY2017Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	246529000	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1648964000	USD
CY2017Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1197852000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4638232000	USD
CY2017Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4789713000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	1807421000	USD
CY2017Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	1690805000	USD
CY2018Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	2325976000	USD
CY2017Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	2452536000	USD
CY2018Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	706703000	USD
CY2017Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	674784000	USD
CY2018Q4	us-gaap	Defined Benefit Pension Plan Liabilities Noncurrent DefinedBenefitPensionPlanLiabilitiesNoncurrent	443170000	USD
CY2017Q4	us-gaap	Defined Benefit Pension Plan Liabilities Noncurrent DefinedBenefitPensionPlanLiabilitiesNoncurrent	327300000	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	147640000	USD
CY2017Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	205575000	USD
CY2018Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	22517000	USD
CY2017Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	13115000	USD
CY2018Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	24531000	USD
CY2017Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	37170000	USD
CY2017Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	148909000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	137153000	USD
CY2017Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	113996000	USD
CY2018Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	212785000	USD
CY2017Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	231597000	USD
CY2018Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	200405000	USD
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-45002000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	5222915000	USD
CY2018Q4	us-gaap	Deferred Credits And Other Liabilities DeferredCreditsAndOtherLiabilities	6028301000	USD
CY2017Q4	us-gaap	Deferred Credits And Other Liabilities DeferredCreditsAndOtherLiabilities	5895787000	USD
CY2018Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2017Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2018Q4	us-gaap	Common Stock Value CommonStockValue	2634265000	USD
CY2017Q4	us-gaap	Common Stock Value CommonStockValue	2614805000	USD
CY2018Q4	us-gaap	Treasury Stock Value TreasuryStockValue	4825000	USD
CY2017Q4	us-gaap	Treasury Stock Value TreasuryStockValue	5624000	USD
CY2018Q4	us-gaap	Common Stock Value Outstanding CommonStockValueOutstanding	2629440000	USD
CY2017Q4	us-gaap	Common Stock Value Outstanding CommonStockValueOutstanding	2609181000	USD
CY2018Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2641183000	USD
CY2017Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2442511000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-47708000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	5006690000	USD
CY2018Q4	us-gaap	Minority Interest MinorityInterest	125790000	USD
CY2017Q4	us-gaap	Minority Interest MinorityInterest	129040000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5348705000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5135730000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	17664202000	USD
CY2017Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	17019082000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	530540000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	507949000	USD
CY2016	us-gaap	Profit Loss ProfitLoss	461527000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	650955000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	610629000	USD
CY2016	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	565011000	USD
CY2018	us-gaap	Increase Decrease In Regulatory Clause Revenue IncreaseDecreaseInRegulatoryClauseRevenue	-78277000	USD
CY2017	us-gaap	Increase Decrease In Regulatory Clause Revenue IncreaseDecreaseInRegulatoryClauseRevenue	-48405000	USD
CY2016	us-gaap	Increase Decrease In Regulatory Clause Revenue IncreaseDecreaseInRegulatoryClauseRevenue	-60303000	USD
CY2018	pnw	Increase Decrease Deferred Fuel And Purchased Power Amortization IncreaseDecreaseDeferredFuelAndPurchasedPowerAmortization	116750000	USD
CY2017	pnw	Increase Decrease Deferred Fuel And Purchased Power Amortization IncreaseDecreaseDeferredFuelAndPurchasedPowerAmortization	-14767000	USD
CY2016	pnw	Increase Decrease Deferred Fuel And Purchased Power Amortization IncreaseDecreaseDeferredFuelAndPurchasedPowerAmortization	38152000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	52319000	USD
CY2017	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	47011000	USD
CY2016	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	42140000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	117355000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	248164000	USD
CY2016	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	206870000	USD
CY2018	pnw	Deferred Investment Tax Credit Expense DeferredInvestmentTaxCreditExpense	-5170000	USD
CY2017	pnw	Deferred Investment Tax Credit Expense DeferredInvestmentTaxCreditExpense	-4587000	USD
CY2016	pnw	Deferred Investment Tax Credit Expense DeferredInvestmentTaxCreditExpense	23082000	USD
CY2018	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	USD
CY2017	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	373000	USD
CY2016	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	403000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	19547000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	20502000	USD
CY2016	us-gaap	Share Based Compensation ShareBasedCompensation	18883000	USD
CY2018	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-37530000	USD
CY2017	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	93797000	USD
CY2016	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	2489000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Asset IncreaseDecreaseInContractWithCustomerAsset	24736000	USD
CY2017	us-gaap	Increase Decrease In Contract With Customer Asset IncreaseDecreaseInContractWithCustomerAsset	4485000	USD
CY2016	us-gaap	Increase Decrease In Contract With Customer Asset IncreaseDecreaseInContractWithCustomerAsset	11709000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	6103000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	6683000	USD
CY2016	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	1491000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	0	USD
CY2017	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-3751000	USD
CY2016	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	3162000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-33844000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	10580000	USD
CY2016	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	23324000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-14602000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-23769000	USD
CY2016	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-66917000	USD
CY2018	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	6597000	USD
CY2017	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	9982000	USD
CY2016	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	447000	USD
CY2018	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	28174000	USD
CY2017	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	19154000	USD
CY2016	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	29594000	USD
CY2018	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	-143000	USD
CY2017	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	300000	USD
CY2016	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	-673000	USD
CY2018	pnw	Change In Margin And Collateral Accounts Liabilities ChangeInMarginAndCollateralAccountsLiabilities	-2211000	USD
CY2017	pnw	Change In Margin And Collateral Accounts Liabilities ChangeInMarginAndCollateralAccountsLiabilities	-533000	USD
CY2016	pnw	Change In Margin And Collateral Accounts Liabilities ChangeInMarginAndCollateralAccountsLiabilities	17735000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	-1235000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	5891000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	1628000	USD
CY2018	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	-109284000	USD
CY2017	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	45764000	USD
CY2016	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	14682000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-78604000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	68480000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	60163000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-48958000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-29980000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-82793000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1277144000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1118036000	USD
CY2016	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1023390000	USD
CY2018	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1178169000	USD
CY2017	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1408774000	USD
CY2016	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1275472000	USD
CY2018	us-gaap	Proceeds From Contribution In Aid Of Construction ProceedsFromContributionInAidOfConstruction	27716000	USD
CY2017	us-gaap	Proceeds From Contribution In Aid Of Construction ProceedsFromContributionInAidOfConstruction	23708000	USD
CY2016	us-gaap	Proceeds From Contribution In Aid Of Construction ProceedsFromContributionInAidOfConstruction	64296000	USD
CY2018	us-gaap	Allowance For Funds Used During Construction Investing Activities AllowanceForFundsUsedDuringConstructionInvestingActivities	-25180000	USD
CY2017	us-gaap	Allowance For Funds Used During Construction Investing Activities AllowanceForFundsUsedDuringConstructionInvestingActivities	-22112000	USD
CY2016	us-gaap	Allowance For Funds Used During Construction Investing Activities AllowanceForFundsUsedDuringConstructionInvestingActivities	-19970000	USD
CY2018	us-gaap	Proceeds From Decommissioning Fund ProceedsFromDecommissioningFund	653033000	USD
CY2017	us-gaap	Proceeds From Decommissioning Fund ProceedsFromDecommissioningFund	542246000	USD
CY2016	us-gaap	Proceeds From Decommissioning Fund ProceedsFromDecommissioningFund	633410000	USD
CY2018	us-gaap	Payments To Invest In Decommissioning Fund PaymentsToInvestInDecommissioningFund	672165000	USD
CY2017	us-gaap	Payments To Invest In Decommissioning Fund PaymentsToInvestInDecommissioningFund	544527000	USD
CY2016	us-gaap	Payments To Invest In Decommissioning Fund PaymentsToInvestInDecommissioningFund	635691000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1941000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	19078000	USD
CY2016	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	18651000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1192824000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1428537000	USD
CY2016	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1252078000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	445245000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	848239000	USD
CY2016	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	693151000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	182000000	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	125000000	USD
CY2016	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	370430000	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-7000000	USD
CY2017	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-107800000	USD
CY2018	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	57000000	USD
CY2017	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	32000000	USD
CY2016	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	308892000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	289793000	USD
CY2016	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	274229000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	-5055000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	-13390000	USD
CY2018	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-8126000	USD
CY2017	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	5011000	USD
CY2016	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-30607000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	13892000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	8881000	USD
CY2016	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	137200000	USD
CY2018	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	45000000	USD
CY2017	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	58000000	USD
CY2016	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	40000000	USD
CY2016	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	-4867000	USD
CY2018	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	22744000	USD
CY2017	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	22744000	USD
CY2016	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	22744000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-92446000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	315512000	USD
CY2016	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	198081000	USD
CY2015Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	39488000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	5766000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	13892000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	8881000	USD
CY2015Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4719457000	USD
CY2016	us-gaap	Profit Loss ProfitLoss	461527000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	926000	USD
CY2016	us-gaap	Dividends Common Stock DividendsCommonStock	284765000	USD
CY2016	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	13982000	USD
CY2016	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	9087000	USD
CY2016	us-gaap	Stock Issued During Period Value Treasury Stock Reissued StockIssuedDuringPeriodValueTreasuryStockReissued	10760000	USD
CY2015Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	45855000	USD
CY2016	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	22743000	USD
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4935912000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	507949000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1180000	USD
CY2017	us-gaap	Dividends Common Stock DividendsCommonStock	301492000	USD
CY2017	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	18775000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	17755000	USD
CY2017	us-gaap	Stock Issued During Period Value Treasury Stock Reissued StockIssuedDuringPeriodValueTreasuryStockReissued	16264000	USD
CY2017	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	22743000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5135730000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	530540000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	5846000	USD
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	320927000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	19460000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	10338000	USD
CY2018	us-gaap	Stock Issued During Period Value Treasury Stock Reissued StockIssuedDuringPeriodValueTreasuryStockReissued	11137000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	22743000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5348705000	USD
CY2018	us-gaap	Use Of Estimates UseOfEstimates	Accounting Records and Use of Estimates<div style="line-height:120%;font-size:11.5pt;"><span style="font-family:inherit;font-size:11.5pt;"> </span></div><div style="line-height:120%;text-indent:48px;font-size:11.5pt;"><span style="font-family:inherit;font-size:11.5pt;">Our accounting records are maintained in accordance with accounting principles generally accepted in the United States of America ("GAAP"). The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.</span></div><br/>
CY2018	us-gaap	Cost Of Goods And Services Sold Depreciation CostOfGoodsAndServicesSoldDepreciation	486000000	USD
CY2017	us-gaap	Cost Of Goods And Services Sold Depreciation CostOfGoodsAndServicesSoldDepreciation	453000000	USD
CY2016	us-gaap	Cost Of Goods And Services Sold Depreciation CostOfGoodsAndServicesSoldDepreciation	422000000	USD
CY2018	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0281
CY2017	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0280
CY2016	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0266
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.0703
CY2017	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.0668
CY2016	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.0717
CY2017	us-gaap	Interest Paid Net InterestPaidNet	189288000	USD
CY2016	us-gaap	Interest Paid Net InterestPaidNet	184462000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	132620000	USD
CY2017	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	130404000	USD
CY2016	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	114855000	USD
CY2018	pnw	Income Tax Percentage Likelihood Largest Tax Benefit Amountis Realized IncomeTaxPercentageLikelihoodLargestTaxBenefitAmountisRealized	0.50
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	21173000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	2186000	USD
CY2016	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	9956000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	208479000	USD
CY2018Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	82675000	USD
CY2017Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	77667000	USD
CY2016Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	72926000	USD
CY2018	us-gaap	Noncash Or Part Noncash Divestiture Amount Of Consideration Received1 NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1	68907000	USD
CY2017	us-gaap	Noncash Or Part Noncash Divestiture Amount Of Consideration Received1 NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1	0	USD
CY2016	us-gaap	Noncash Or Part Noncash Divestiture Amount Of Consideration Received1 NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1	0	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	68000000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	72000000	USD
CY2016	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	58000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	58000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	47000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	34000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	25000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	22000000	USD
CY2018	us-gaap	Finite Lived Intangible Assets Remaining Amortization Period1 FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1	P8Y
CY2018Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	194000000	USD
CY2018Q4	pnw	Lease Liability LeaseLiability	119000000	USD
CY2018Q1	pnw	Public Utilities Ballot Initiative Proposed Required Energy Supply From Renewable Sources Percent PublicUtilitiesBallotInitiativeProposedRequiredEnergySupplyFromRenewableSourcesPercent	0.50
CY2018Q4	pnw	Regulatory Asset Including Deferred Fuel And Purchased Power Regulatory Asset Current RegulatoryAssetIncludingDeferredFuelAndPurchasedPowerRegulatoryAssetCurrent	166902000	USD
CY2018Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1342941000	USD
CY2017Q4	pnw	Regulatory Asset Including Deferred Fuel And Purchased Power Regulatory Asset Current RegulatoryAssetIncludingDeferredFuelAndPurchasedPowerRegulatoryAssetCurrent	248088000	USD
CY2017Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1202302000	USD
CY2018Q4	pnw	Regulatory Liability Including Deferred Fuel And Purchased Power Regulatory Liability Current RegulatoryLiabilityIncludingDeferredFuelAndPurchasedPowerRegulatoryLiabilityCurrent	165876000	USD
CY2018Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	2325976000	USD
CY2017Q4	pnw	Regulatory Liability Including Deferred Fuel And Purchased Power Regulatory Liability Current RegulatoryLiabilityIncludingDeferredFuelAndPurchasedPowerRegulatoryLiabilityCurrent	100086000	USD
CY2017Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	2452536000	USD
CY2017	pnw	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Change In Tax Rate Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpenseBenefit	1140000000	USD
CY2018Q3	pnw	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Change In Tax Rate Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpenseBenefit	11000000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	41966000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	36075000	USD
CY2015Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	34447000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	3436000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	2937000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	2695000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	2696000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	4783000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	886000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1764000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1829000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1953000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2016	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	5603000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	USD
CY2016	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	40731000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	41966000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	36075000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	19504000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	16373000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	11313000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	-780000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	577000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	529000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1130000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1910000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1333000	USD
CY2018Q4	pnw	Unrecognized Tax Benefits Interest On Income Taxes Receivable UnrecognizedTaxBenefitsInterestOnIncomeTaxesReceivable	1000000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	18375000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	11624000	USD
CY2016	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	8630000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	3342000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	3052000	USD
CY2016	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1259000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	21717000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	14676000	USD
CY2016	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	9889000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	94721000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	223729000	USD
CY2016	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	201743000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	17464000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	19867000	USD
CY2016	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	24779000	USD
CY2018	pnw	Deferred Income Tax Expense Benefit Continuing And Discontinued Operations DeferredIncomeTaxExpenseBenefitContinuingAndDiscontinuedOperations	112185000	USD
CY2017	pnw	Deferred Income Tax Expense Benefit Continuing And Discontinued Operations DeferredIncomeTaxExpenseBenefitContinuingAndDiscontinuedOperations	243596000	USD
CY2016	pnw	Deferred Income Tax Expense Benefit Continuing And Discontinued Operations DeferredIncomeTaxExpenseBenefitContinuingAndDiscontinuedOperations	226522000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	133902000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	258272000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	236411000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	139533000	USD
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	268177000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	6742000	USD
CY2017	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	6715000	USD
CY2016	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	5887000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-3325000	USD
CY2017	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1016000	USD
CY2016	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	244278000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	16411000	USD
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	14897000	USD
CY2016	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	16311000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	7879000	USD
CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	0	USD
CY2016	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	0	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-1804000	USD
CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-6659000	USD
CY2016	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-2951000	USD
CY2018	pnw	Effective Income Tax Rate Reconciliation Excess Deferred Income Taxes Amount EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxesAmount	-6725000	USD
CY2017	pnw	Effective Income Tax Rate Reconciliation Excess Deferred Income Taxes Amount EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxesAmount	9348000	USD
CY2016	pnw	Effective Income Tax Rate Reconciliation Excess Deferred Income Taxes Amount EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxesAmount	0	USD
CY2018	pnw	Income Tax Reconciliation Allowance For Equity Funds Used During Construction IncomeTaxReconciliationAllowanceForEquityFundsUsedDuringConstruction	7231000	USD
CY2017	pnw	Income Tax Reconciliation Allowance For Equity Funds Used During Construction IncomeTaxReconciliationAllowanceForEquityFundsUsedDuringConstruction	12937000	USD
CY2016	pnw	Income Tax Reconciliation Allowance For Equity Funds Used During Construction IncomeTaxReconciliationAllowanceForEquityFundsUsedDuringConstruction	11724000	USD
CY2018	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	4094000	USD
CY2017	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	6823000	USD
CY2016	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	6823000	USD
CY2016	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	3207000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	133902000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	258272000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	236411000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	15785000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	25103000	USD
CY2018Q4	pnw	Deferred Tax Assets Excess Deferred Income Taxes DeferredTaxAssetsExcessDeferredIncomeTaxes	376869000	USD
CY2017Q4	pnw	Deferred Tax Assets Excess Deferred Income Taxes DeferredTaxAssetsExcessDeferredIncomeTaxes	376906000	USD
CY2018Q4	pnw	Deferred Tax Assets Regulatory Liabilities Asset Retirement Obligation And Removal Costs DeferredTaxAssetsRegulatoryLiabilitiesAssetRetirementObligationAndRemovalCosts	117201000	USD
CY2017Q4	pnw	Deferred Tax Assets Regulatory Liabilities Asset Retirement Obligation And Removal Costs DeferredTaxAssetsRegulatoryLiabilitiesAssetRetirementObligationAndRemovalCosts	135847000	USD
CY2018Q4	pnw	Deferred Tax Assets Regulatory Liabilities Unamortized Investment Tax Credits DeferredTaxAssetsRegulatoryLiabilitiesUnamortizedInvestmentTaxCredits	53284000	USD
CY2017Q4	pnw	Deferred Tax Assets Regulatory Liabilities Unamortized Investment Tax Credits DeferredTaxAssetsRegulatoryLiabilitiesUnamortizedInvestmentTaxCredits	54661000	USD
CY2018Q4	pnw	Deferred Tax Assets Regulatory Liabilities Other Postretirement Benefits DeferredTaxAssetsRegulatoryLiabilitiesOtherPostretirementBenefits	40532000	USD
CY2017Q4	pnw	Deferred Tax Assets Regulatory Liabilities Other Postretirement Benefits DeferredTaxAssetsRegulatoryLiabilitiesOtherPostretirementBenefits	47021000	USD
CY2018Q4	pnw	Deferred Tax Assets Regulatory Liabilities Other DeferredTaxAssetsRegulatoryLiabilitiesOther	40380000	USD
CY2017	us-gaap	Variable Lease Cost VariableLeaseCost	100000000	USD
CY2016	us-gaap	Operating Lease Cost OperatingLeaseCost	82000000	USD
CY2018	us-gaap	Variable Lease Cost VariableLeaseCost	109000000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	491000	USD
CY2018Q4	pnw	Deferred Tax Liabilities Other Postretirement Assets DeferredTaxLiabilitiesOtherPostretirementAssets	57697000	USD
CY2017Q4	pnw	Deferred Tax Liabilities Other Postretirement Assets DeferredTaxLiabilitiesOtherPostretirementAssets	66134000	USD
CY2018Q4	pnw	Deferred Tax Liabilities Regulatory Assets Allowance For Equity Funds Used During Construction DeferredTaxLiabilitiesRegulatoryAssetsAllowanceForEquityFundsUsedDuringConstruction	39086000	USD
CY2017Q4	pnw	Deferred Tax Liabilities Regulatory Assets Allowance For Equity Funds Used During Construction DeferredTaxLiabilitiesRegulatoryAssetsAllowanceForEquityFundsUsedDuringConstruction	36365000	USD
CY2018Q4	pnw	Deferred Tax Liabilities Regulatory Assets Deferred Fuel And Purchased Power Mark To Market DeferredTaxLiabilitiesRegulatoryAssetsDeferredFuelAndPurchasedPowerMarkToMarket	23086000	USD
CY2017Q4	pnw	Deferred Tax Liabilities Regulatory Assets Deferred Fuel And Purchased Power Mark To Market DeferredTaxLiabilitiesRegulatoryAssetsDeferredFuelAndPurchasedPowerMarkToMarket	40778000	USD
CY2017Q4	pnw	Deferred Tax Assets Regulatory Liabilities Other DeferredTaxAssetsRegulatoryLiabilitiesOther	37489000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	112019000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	83126000	USD
CY2018Q4	pnw	Deferred Tax Assets Coal Reclamation Liabilities DeferredTaxAssetsCoalReclamationLiabilities	47508000	USD
CY2017Q4	pnw	Deferred Tax Assets Coal Reclamation Liabilities DeferredTaxAssetsCoalReclamationLiabilities	45802000	USD
CY2018Q4	pnw	Deferred Tax Assets Renewable Energy Incentives DeferredTaxAssetsRenewableEnergyIncentives	30779000	USD
CY2017Q4	pnw	Deferred Tax Assets Renewable Energy Incentives DeferredTaxAssetsRenewableEnergyIncentives	33546000	USD
CY2018Q4	pnw	Deferred Tax Assets Credit And Loss Carryforwards DeferredTaxAssetsCreditAndLossCarryforwards	1755000	USD
CY2017Q4	pnw	Deferred Tax Assets Credit And Loss Carryforwards DeferredTaxAssetsCreditAndLossCarryforwards	53946000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	58820000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	56630000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	894932000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	950077000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2277724000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2220886000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	237000	USD
CY2018Q4	pnw	Deferred Tax Liabilities Regulatory Assets Pension And Other Postretirement Benefits DeferredTaxLiabilitiesRegulatoryAssetsPensionAndOtherPostretirementBenefits	181504000	USD
CY2017Q4	pnw	Deferred Tax Liabilities Regulatory Assets Pension And Other Postretirement Benefits DeferredTaxLiabilitiesRegulatoryAssetsPensionAndOtherPostretirementBenefits	142848000	USD
CY2018Q4	pnw	Deferred Tax Liabilities Regulatory Assets Retired Power Plan Costs DeferredTaxLiabilitiesRegulatoryAssetsRetiredPowerPlanCosts	48348000	USD
CY2017Q4	pnw	Deferred Tax Liabilities Regulatory Assets Retired Power Plan Costs DeferredTaxLiabilitiesRegulatoryAssetsRetiredPowerPlanCosts	53611000	USD
CY2018Q4	pnw	Deferred Tax Liabilities Regulatory Assets Other DeferredTaxLiabilitiesRegulatoryAssetsOther	72096000	USD
CY2017Q4	pnw	Deferred Tax Liabilities Regulatory Assets Other DeferredTaxLiabilitiesRegulatoryAssetsOther	74423000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2575000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	5346000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	2702353000	USD
CY2017Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	2640882000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1807421000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1690805000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards General Business DeferredTaxAssetsTaxCreditCarryforwardsGeneralBusiness	14000000	USD
CY2018	pnw	Increase Decrease In Deferred Income Taxes Due To Regulation Adoption IncreaseDecreaseInDeferredIncomeTaxesDueToRegulationAdoption	-19000000	USD
CY2016	pnw	Defined Benefit Plan Post65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Costs DefinedBenefitPlanPost65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitCosts	0.0500
CY2018	pnw	Defined Benefit Plan Ultimate Health Care Cost Trend Rateusedin Calculating Benefit Obligations DefinedBenefitPlanUltimateHealthCareCostTrendRateusedinCalculatingBenefitObligations	0.0475
CY2017	pnw	Defined Benefit Plan Ultimate Health Care Cost Trend Rateusedin Calculating Benefit Obligations DefinedBenefitPlanUltimateHealthCareCostTrendRateusedinCalculatingBenefitObligations	0.0475
CY2018Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0475
CY2017Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0500
CY2016Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0500
CY2018	pnw	Defined Benefit Plan Pre65 Participant Periodafterwhich Rate Reaches Ultimate Trend Rateusedin Calculating Benefit Obligations DefinedBenefitPlanPre65ParticipantPeriodafterwhichRateReachesUltimateTrendRateusedinCalculatingBenefitObligations	P7Y
CY2017	pnw	Defined Benefit Plan Pre65 Participant Periodafterwhich Rate Reaches Ultimate Trend Rateusedin Calculating Benefit Obligations DefinedBenefitPlanPre65ParticipantPeriodafterwhichRateReachesUltimateTrendRateusedinCalculatingBenefitObligations	P8Y
CY2018	pnw	Defined Benefit Plan Pre65 Participant Periodafterwhich Rate Reaches Ultimate Trend Rateusedin Calculating Benefit Costs DefinedBenefitPlanPre65ParticipantPeriodafterwhichRateReachesUltimateTrendRateusedinCalculatingBenefitCosts	P8Y
CY2017	pnw	Defined Benefit Plan Pre65 Participant Periodafterwhich Rate Reaches Ultimate Trend Rateusedin Calculating Benefit Costs DefinedBenefitPlanPre65ParticipantPeriodafterwhichRateReachesUltimateTrendRateusedinCalculatingBenefitCosts	P4Y
CY2016	pnw	Defined Benefit Plan Pre65 Participant Periodafterwhich Rate Reaches Ultimate Trend Rateusedin Calculating Benefit Costs DefinedBenefitPlanPre65ParticipantPeriodafterwhichRateReachesUltimateTrendRateusedinCalculatingBenefitCosts	P4Y
CY2016	us-gaap	Variable Lease Cost VariableLeaseCost	88000000	USD
CY2018Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	54000000	USD
CY2018	us-gaap	Operating Lease Cost OperatingLeaseCost	47000000	USD
CY2018Q4	pnw	Defined Benefit Plan Partnership Funding Commitments Maximum Contribution Amount DefinedBenefitPlanPartnershipFundingCommitmentsMaximumContributionAmount	75000000	USD
CY2018	pnw	Defined Benefit Plan Partnership Funding Commitments Funded Amount DefinedBenefitPlanPartnershipFundingCommitmentsFundedAmount	62000000	USD
CY2016	us-gaap	Lease Cost LeaseCost	16000000	USD
CY2017	us-gaap	Operating Lease Cost OperatingLeaseCost	60000000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4638232000	USD
CY2017Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4789713000	USD
CY2018Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	5138232000	USD
CY2018Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	5233563000	USD
CY2017Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	4871713000	USD
CY2017Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	5304956000	USD
CY2018Q4	pnw	Defined Benefit Plan Amountof Other Postretirement Benefit Trust Assetsfor Union Employee Medical Costs DefinedBenefitPlanAmountofOtherPostretirementBenefitTrustAssetsforUnionEmployeeMedicalCosts	186000000	USD
CY2018Q4	pnw	Defined Benefit Plan Amountof Other Postretirement Benefit Trust Assetsfor Union Employee Medical Costs DefinedBenefitPlanAmountofOtherPostretirementBenefitTrustAssetsforUnionEmployeeMedicalCosts	186000000	USD
CY2018	us-gaap	Lease Cost LeaseCost	18000000	USD
CY2017	us-gaap	Lease Cost LeaseCost	18000000	USD
CY2017	pnw	Defined Benefit Plan Post65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Costs DefinedBenefitPlanPost65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitCosts	0.0500
CY2016	pnw	Defined Benefit Plan Pre65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Costs DefinedBenefitPlanPre65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitCosts	0.0700
CY2018	pnw	Defined Benefit Plan Post65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Obligation DefinedBenefitPlanPost65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitObligation	0.0475
CY2017	pnw	Defined Benefit Plan Post65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Obligation DefinedBenefitPlanPost65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitObligation	0.0475
CY2018	pnw	Defined Benefit Plan Post65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Costs DefinedBenefitPlanPost65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitCosts	0.0475
CY2018Q4	us-gaap	Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Rate Of Compensation Increase DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease	0.0400
CY2017Q4	us-gaap	Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Rate Of Compensation Increase DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease	0.0400
CY2018	pnw	Defined Benefit Plan Pre65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Obligation DefinedBenefitPlanPre65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitObligation	0.0700
CY2017	pnw	Defined Benefit Plan Pre65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Obligation DefinedBenefitPlanPre65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitObligation	0.0700
CY2018	pnw	Defined Benefit Plan Pre65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Costs DefinedBenefitPlanPre65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitCosts	0.0700
CY2017	pnw	Defined Benefit Plan Pre65 Health Care Cost Trend Rate Assumedfor Next Fiscal Year Usedin Calculating Benefit Costs DefinedBenefitPlanPre65HealthCareCostTrendRateAssumedforNextFiscalYearUsedinCalculatingBenefitCosts	0.0700
CY2018Q1	us-gaap	Revenues Revenues	692714000	USD
CY2018Q2	us-gaap	Revenues Revenues	974123000	USD
CY2018Q3	us-gaap	Revenues Revenues	1268034000	USD
CY2018Q4	us-gaap	Revenues Revenues	756376000	USD
CY2018	us-gaap	Revenues Revenues	3691247000	USD
CY2018Q1	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	265682000	USD
CY2018Q2	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	268397000	USD
CY2018Q3	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	246545000	USD
CY2018Q4	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	256120000	USD
CY2018	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	1036744000	USD
CY2018Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	31334000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	242162000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	433307000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	66884000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	909763000	USD
CY2017Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4211000	USD
CY2017Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	88967000	USD
CY2017Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	144319000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	773687000	USD
CY2018Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1265000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	44039000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	84333000	USD
CY2018Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6795000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	133902000	USD
CY2018Q1	us-gaap	Profit Loss ProfitLoss	8094000	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	171612000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	319885000	USD
CY2018Q4	us-gaap	Profit Loss ProfitLoss	30949000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	530540000	USD
CY2018Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	3221000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	166738000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	315012000	USD
CY2018Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	26076000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	511047000	USD
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.03
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.49
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.81
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.23
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.56
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.03
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.48
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.80
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.23
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.54
CY2017Q1	us-gaap	Revenues Revenues	677728000	USD
CY2017Q2	us-gaap	Revenues Revenues	944587000	USD
CY2017Q3	us-gaap	Revenues Revenues	1183322000	USD
CY2017Q4	us-gaap	Revenues Revenues	759659000	USD
CY2017	us-gaap	Revenues Revenues	3565296000	USD
CY2017Q1	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	226071000	USD
CY2017Q2	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	220985000	USD
CY2017Q3	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	230839000	USD
CY2017Q4	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	271212000	USD
CY2017	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	949107000	USD
CY2017Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	67411000	USD
CY2017Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	297257000	USD
CY2017Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	459548000	USD
CY2017Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	85547000	USD
CY2017Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	20775000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	258272000	USD
CY2017Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	276072000	USD
CY2017Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	21629000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	488456000	USD
CY2017Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.21
CY2017Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.50
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.47
CY2017Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.19
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.37
CY2017Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.21
CY2017Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.49
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.46
CY2017Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.19
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.35
CY2017Q1	us-gaap	Profit Loss ProfitLoss	28185000	USD
CY2017Q2	us-gaap	Profit Loss ProfitLoss	172317000	USD
CY2017Q3	us-gaap	Profit Loss ProfitLoss	280945000	USD
CY2017Q4	us-gaap	Profit Loss ProfitLoss	26502000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	507949000	USD
CY2017Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	23312000	USD
CY2017Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	167443000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	1200000	USD
CY2018Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	2029000	USD
CY2018Q4	us-gaap	Derivative Assets DerivativeAssets	1113000	USD
CY2018Q4	pnw	Decommissioning Fund Investments Fair Value Net Pending Securities Salesand Purchases DecommissioningFundInvestmentsFairValueNetPendingSecuritiesSalesandPurchases	398953000	USD
CY2018Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	851134000	USD
CY2018Q4	pnw	Special Use Fund Investments Other Net Fair Value Pending Salesand Purchases SpecialUseFundInvestmentsOtherNetFairValuePendingSalesandPurchases	593000	USD
CY2018Q4	pnw	Special Use Fund Investments Other Gross Fair Value SpecialUseFundInvestmentsOtherGrossFairValue	236101000	USD
CY2018Q4	pnw	Assets Fair Value Gross Liabilityand Net Pending Securities Salesand Purchases AssetsFairValueGrossLiabilityandNetPendingSecuritiesSalesandPurchases	397517000	USD
CY2018Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	1089548000	USD
CY2018Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	875000	USD
CY2018Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	60037000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	10630000	USD
CY2017Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	4737000	USD
CY2017Q4	us-gaap	Derivative Assets DerivativeAssets	1982000	USD
CY2017Q4	pnw	Decommissioning Fund Investments Fair Value Net Pending Securities Salesand Purchases DecommissioningFundInvestmentsFairValueNetPendingSecuritiesSalesandPurchases	417499000	USD
CY2017Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	871000000	USD
CY2017Q4	pnw	Special Use Fund Investments Other Net Fair Value Pending Salesand Purchases SpecialUseFundInvestmentsOtherNetFairValuePendingSalesandPurchases	525000	USD
CY2017Q4	pnw	Special Use Fund Investments Other Gross Fair Value SpecialUseFundInvestmentsOtherGrossFairValue	32542000	USD
CY2017Q4	pnw	Assets Fair Value Gross Liabilityand Net Pending Securities Salesand Purchases AssetsFairValueGrossLiabilityandNetPendingSecuritiesSalesandPurchases	413287000	USD
CY2017Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	916154000	USD
CY2017Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	1516000	USD
CY2017Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	96422000	USD
CY2017	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Transfers Out Of Level3 FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3	-46982000	USD
CY2018Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	-8214000	USD
CY2017Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	-18256000	USD
CY2017Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	-18256000	USD
CY2016Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	-47406000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Gain Loss Included In Earnings FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings	0	USD
CY2017	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Gain Loss Included In Earnings FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings	0	USD
CY2018	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisGainLossIncludedInOtherComprehensiveIncomeLoss	0	USD
CY2017	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisGainLossIncludedInOtherComprehensiveIncomeLoss	3000	USD
CY2018	pnw	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Derivative Gain Loss Deferred As Regulatory Asset Or Liability FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisDerivativeGainLossDeferredAsRegulatoryAssetOrLiability	-1130000	USD
CY2017	pnw	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Derivative Gain Loss Deferred As Regulatory Asset Or Liability FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisDerivativeGainLossDeferredAsRegulatoryAssetOrLiability	-13643000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Settlements FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements	787000	USD
CY2017	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Settlements FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements	-5834000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Transfers Into Level3 FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3	-12830000	USD
CY2017	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Transfers Into Level3 FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3	-10026000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Transfers Out Of Level3 FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3	-24789000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Change In Unrealized Gain Loss FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	0	USD
CY2017	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Change In Unrealized Gain Loss FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	0	USD
CY2018	pnw	Fair Value Measurement Inter Level Transfers Amount FairValueMeasurementInterLevelTransfersAmount	0	USD
CY2018Q4	us-gaap	Debt Instrument Interest Rate Stated Percentage DebtInstrumentInterestRateStatedPercentage	0.039
CY2018Q4	us-gaap	Notes Receivable Net NotesReceivableNet	61000000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	511047000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	488456000	USD
CY2016	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	442034000	USD
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	112129000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	111839000	shares
CY2016	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	111409000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	421000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	528000	shares
CY2016	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	637000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	112550000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	112367000	shares
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	112046000	shares
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.56
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.37
CY2016	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.97
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.54
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.35
CY2016	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.95
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	20000000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	21000000	USD
CY2016	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	19000000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	7000000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	15000000	USD
CY2016	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	10000000	USD
CY2018Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	9000000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P2Y
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	24000000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	22000000	USD
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	22000000	USD
CY2018	pnw	Share Based Compensation Arrangement By Share Based Payment Award Number Of Performance Elements Criteria ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfPerformanceElementsCriteria	2	performance_criteria
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
CY2017	us-gaap	Derivative Nonmonetary Notional Amount Energy Measure DerivativeNonmonetaryNotionalAmountEnergyMeasure	583000	MWh
CY2018	us-gaap	Derivative Nonmonetary Notional Amount Volume DerivativeNonmonetaryNotionalAmountVolume	218	Bcf
CY2017	us-gaap	Derivative Nonmonetary Notional Amount Volume DerivativeNonmonetaryNotionalAmountVolume	240	Bcf
CY2018	us-gaap	Derivative Nonmonetary Notional Amount Energy Measure DerivativeNonmonetaryNotionalAmountEnergyMeasure	250000	MWh
CY2018	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	17966000	USD
CY2017	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	21539000	USD
CY2018	us-gaap	Investment Income Interest InvestmentIncomeInterest	8647000	USD
CY2017	us-gaap	Investment Income Interest InvestmentIncomeInterest	3497000	USD
CY2016	us-gaap	Investment Income Interest InvestmentIncomeInterest	884000	USD
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	16153000	USD
CY2017	us-gaap	Gain Loss On Investments GainLossOnInvestments	354000	USD
CY2016	us-gaap	Gain Loss On Investments GainLossOnInvestments	0	USD
CY2018	pnw	Miscellaneous Other Nonoperating Income MiscellaneousOtherNonoperatingIncome	96000	USD
CY2017	pnw	Miscellaneous Other Nonoperating Income MiscellaneousOtherNonoperatingIncome	155000	USD
CY2016	pnw	Miscellaneous Other Nonoperating Income MiscellaneousOtherNonoperatingIncome	17000	USD
CY2018	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	24896000	USD
CY2017	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	4006000	USD
CY2016	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	901000	USD
CY2018	pnw	Nonoperating Costs NonoperatingCosts	10076000	USD
CY2017	pnw	Nonoperating Costs NonoperatingCosts	11749000	USD
CY2016	pnw	Nonoperating Costs NonoperatingCosts	9235000	USD
CY2018	us-gaap	Loss On Sale Of Investments LossOnSaleOfInvestments	417000	USD
CY2017	us-gaap	Loss On Sale Of Investments LossOnSaleOfInvestments	4113000	USD
CY2016	us-gaap	Loss On Sale Of Investments LossOnSaleOfInvestments	1747000	USD
CY2018	pnw	Miscellaneous Other Nonoperating Expense MiscellaneousOtherNonoperatingExpense	7473000	USD
CY2017	pnw	Miscellaneous Other Nonoperating Expense MiscellaneousOtherNonoperatingExpense	5677000	USD
CY2016	pnw	Miscellaneous Other Nonoperating Expense MiscellaneousOtherNonoperatingExpense	4355000	USD
CY2016	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	15337000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3691247000	USD
CY2018	pnw	Regulatory Cost Recovery Revenue RegulatoryCostRecoveryRevenue	47000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-6473000	USD
CY2017	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-5293000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	24000	USD
CY2018	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-5822000	USD
CY2018	pnw	Tax Cuts And Jobs Act Of2017 Reclassification From Aoci To Retained Earnings Tax Effect TaxCutsAndJobsActOf2017ReclassificationFromAOCIToRetainedEarningsTaxEffect	-8552000	USD

Files In Submission

Name	View Source	Status
0000764622-19-000019-index-headers.html	Edgar Link	pending
0000764622-19-000019-index.html	Edgar Link	pending
0000764622-19-000019.txt	Edgar Link	pending
0000764622-19-000019-xbrl.zip	Edgar Link	pending
chart-50d1349fe82352d4859.jpg	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
pnw-20181231.xsd	Edgar Link	pending
pnw-20181231_cal.xml	Edgar Link	unprocessable
pnw-20181231_def.xml	Edgar Link	unprocessable
pnw-20181231_lab.xml	Edgar Link	unprocessable
pnw-20181231_pre.xml	Edgar Link	unprocessable
pnw2018123110-k.htm	Edgar Link	pending
pnw2018123110-k_htm.xml	Edgar Link	completed
pnw20181231exhibit10111.htm	Edgar Link	pending
pnw20181231exhibit1042.htm	Edgar Link	pending
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report.css	Edgar Link	pending
sectransmittal22417fo_image1.jpg	Edgar Link	pending
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smap.jpg	Edgar Link	pending

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$PNW
PINNACLE WEST CAPITAL CORP Stock $pnw

2018 Form 10-K Financial Statement

#000076462219000019 Filed on February 22, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$PNW PINNACLE WEST CAPITAL CORP Stock $pnw

2018 Form 10-K Financial Statement

#000076462219000019 Filed on February 22, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$PNW
PINNACLE WEST CAPITAL CORP Stock $pnw