$AVA
AVISTA CORP Stock $ava

$ava Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000156459021007774 Filed on February 24, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue	$364.6M	$372.2M	$1.397B
YoY Change	-2.06%	-6.44%	-3.39%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$1.400M
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$51.10M	$47.60M	$187.3M
YoY Change	7.35%	6.01%	6.64%
% of Gross Profit
Operating Expenses	$291.3M	$293.9M	$1.132B
YoY Change	-0.88%	-4.39%	-0.62%
Operating Profit	$73.31M	$77.18M	$261.1M
YoY Change	-5.02%	-8.01%	-10.63%
Interest Expense	-$25.20M	-$25.20M	$99.72M
YoY Change	0.0%	6.78%	4.57%
% of Operating Profit	-34.38%	-32.65%	38.19%
Other Income/Expense, Net	$5.900M	$2.500M	-$1.458M
YoY Change	136.0%	-266.67%	140.2%
Pretax Income	$54.00M	$54.50M	$162.7M
YoY Change	-0.92%	-7.31%	-18.13%
Income Tax	$3.200M	$8.600M	$26.06M
% Of Pretax Income	5.93%	15.78%	16.02%
Net Earnings	$50.78M	$45.84M	$136.4M
YoY Change	10.76%	66.23%	17.7%
Net Earnings / Revenue	13.93%	12.32%	9.77%
Basic Earnings Per Share			$2.08
Diluted Earnings Per Share	$0.76	$0.70	$2.07
COMMON SHARES
Basic Shares Outstanding	66.93M shares	65.69M shares	65.67M
Diluted Shares Outstanding	67.06M shares	65.85M shares	65.95M

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments	$10.00M	$15.00M	$15.00M
YoY Change	-33.33%	-6.25%	-6.25%
Cash & Equivalents	$9.896M	$14.66M	$15.00M
Short-Term Investments
Other Short-Term Assets	$40.14M	$54.01M	$103.0M
YoY Change	-25.68%	64.3%	33.77%
Inventory	$66.58M	$63.88M	$64.00M
Prepaid Expenses	$19.65M	$17.54M
Receivables	$167.0M	$166.0M	$166.0M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$305.1M	$346.9M	$347.0M
YoY Change	-12.05%	2.78%	2.66%
LONG-TERM ASSETS
Property, Plant & Equipment	$4.918B	$4.649B	$4.649B
YoY Change	5.79%	5.68%	5.68%
Goodwill	$52.43M	$57.67M
YoY Change	-9.1%	0.0%
Intangibles
YoY Change
Long-Term Investments	$51.26M	$29.26M	$110.0M
YoY Change	75.2%	32.18%	18.28%
Other Assets	$23.39M	$23.07M	$619.0M
YoY Change	1.43%	8.4%	-1.43%
Total Long-Term Assets	$5.777B	$5.436B	$5.436B
YoY Change	6.29%	4.99%	5.0%
TOTAL ASSETS
Total Short-Term Assets	$305.1M	$346.9M	$347.0M
Total Long-Term Assets	$5.777B	$5.436B	$5.436B
Total Assets	$6.082B	$5.783B	$5.783B
YoY Change	5.19%	4.86%	4.86%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$110.2M	$108.4M	$108.0M
YoY Change	1.7%	1.01%	0.93%
Accrued Expenses	$35.43M	$32.75M	$75.00M
YoY Change	8.2%	-3.1%	50.0%
Deferred Revenue
YoY Change
Short-Term Debt	$185.8M	$190.0M	$190.0M
YoY Change	-2.21%	80.27%	80.95%
Long-Term Debt Due	$52.00M	$108.0M	$108.0M
YoY Change	-51.85%	-61.01%	-61.01%
Total Short-Term Liabilities	$530.7M	$639.6M	$640.0M
YoY Change	-17.02%	-8.3%	-8.31%
LONG-TERM LIABILITIES
Long-Term Debt	$1.844B	$1.807B	$1.807B
YoY Change	2.03%	17.11%	17.11%
Other Long-Term Liabilities	$201.2M	$71.03M	$1.074B
YoY Change	183.24%	-2.85%	-0.28%
Total Long-Term Liabilities	$2.045B	$71.03M	$2.881B
YoY Change	2778.96%	-2.85%	9.96%
TOTAL LIABILITIES
Total Short-Term Liabilities	$530.7M	$639.6M	$640.0M
Total Long-Term Liabilities	$2.045B	$71.03M	$2.881B
Total Liabilities	$4.143B	$4.009B	$4.009B
YoY Change	3.36%	5.93%	5.92%
SHAREHOLDERS EQUITY
Retained Earnings	$738.8M	$644.6M
YoY Change	14.61%	6.64%
Common Stock	$1.211B	$1.136B
YoY Change	6.53%	0.27%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.939B	$1.773B	$1.773B
YoY Change
Total Liabilities & Shareholders Equity	$6.082B	$5.783B	$5.783B
YoY Change	5.19%	4.86%	4.86%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	$50.78M	$45.84M	$136.4M
YoY Change	10.76%	66.23%	17.7%
Depreciation, Depletion And Amortization	$51.10M	$47.60M	$187.3M
YoY Change	7.35%	6.01%	6.64%
Cash From Operating Activities	$57.70M	-$3.900M	$361.9M
YoY Change	-1579.49%	-103.79%	-11.8%
INVESTING ACTIVITIES
Capital Expenditures	-$121.5M	-$128.2M	$424.4M
YoY Change	-5.23%	3.05%	2.91%
Acquisitions
YoY Change
Other Investing Activities	-$3.600M	-$4.600M	-$756.0K
YoY Change	-21.74%	-36.99%	-117.24%
Cash From Investing Activities	-$125.2M	-$132.7M	-$440.4M
YoY Change	-5.65%	0.76%	1.46%
FINANCING ACTIVITIES
Cash Dividend Paid			$98.05M
YoY Change			6.04%
Common Stock Issuance & Retirement, Net			$1.207M
YoY Change			-102.14%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	62.90M	130.1M	77.03M
YoY Change	-51.65%	326.56%	144.78%
NET CHANGE
Cash From Operating Activities	57.70M	-3.900M	361.9M
Cash From Investing Activities	-125.2M	-132.7M	-$440.4M
Cash From Financing Activities	62.90M	130.1M	77.03M
Net Change In Cash	-4.600M	-6.500M	-1.516M
YoY Change	-29.23%	-506.25%	-119.78%
FREE CASH FLOW
Cash From Operating Activities	$57.70M	-$3.900M	$361.9M
Capital Expenditures	-$121.5M	-$128.2M	$424.4M
Free Cash Flow	$179.2M	$124.3M	-$62.47M
YoY Change	44.17%	-45.29%	2960.51%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value
CY2020	dei	Entity Registrant Name EntityRegistrantName	AVISTA CORPORATION
CY2019Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	us-gaap:Liabilities
CY2020Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	us-gaap:Liabilities
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000104918
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	us-gaap	Lessee Operating Lease Existence Of Option To Extend LesseeOperatingLeaseExistenceOfOptionToExtend	true
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2
CY2020Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2020	ava	Proposed Cumulative Rebate Refund Period ProposedCumulativeRebateRefundPeriod	P2Y
CY2019Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesNoncurrent
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesNoncurrent
CY2020Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesCurrent
CY2019Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesCurrent
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesNoncurrent
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesNoncurrent
CY2020Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	us-gaap:Liabilities
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-03701
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	WA
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	91-0462470
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	1411 East Mission Avenue
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Spokane
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	WA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	99202-2600
CY2020	dei	City Area Code CityAreaCode	509
CY2020	dei	Local Phone Number LocalPhoneNumber	489-0500
CY2020	dei	Security12b Title Security12bTitle	Common Stock
CY2020	dei	Trading Symbol TradingSymbol	AVA
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2019	us-gaap	Pension Contributions PensionContributions	22000000.0
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	629000
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	799000
CY2020	us-gaap	Costs And Expenses CostsAndExpenses	1089191000
CY2019	us-gaap	Costs And Expenses CostsAndExpenses	1135233000
CY2018	us-gaap	Costs And Expenses CostsAndExpenses	1135780000
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	232700000
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	210389000
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	2471363713
CY2019	ava	Regulated Revenues Excluding Alternative Revenue Programs RegulatedRevenuesExcludingAlternativeRevenuePrograms	1323524000
CY2018	ava	Regulated Revenues Excluding Alternative Revenue Programs RegulatedRevenuesExcludingAlternativeRevenuePrograms	1368657000
CY2018	ava	Revenue From Alternative Revenue Programs RevenueFromAlternativeRevenuePrograms	908000
CY2020	us-gaap	Revenues Revenues	1321891000
CY2020	us-gaap	Utilities Operating Expense Products And Services UtilitiesOperatingExpenseProductsAndServices	398509000
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CY2020	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	354614000
CY2019	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	345212000
CY2018	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	318274000
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	19675000
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3718000
CY2020	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	223507000
CY2019	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	205365000
CY2018	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	182877000
CY2020	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	106501000
CY2019	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	105652000
CY2018	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	107295000
CY2020	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	5344000
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CY2018	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	28081000
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	716000
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	261113000
CY2020	ava	Interest Expense Excluding Interest Expense To Related Party InterestExpenseExcludingInterestExpenseToRelatedParty	104348000
CY2019	ava	Interest Expense Excluding Interest Expense To Related Party InterestExpenseExcludingInterestExpenseToRelatedParty	103012000
CY2018	ava	Interest Expense Excluding Interest Expense To Related Party InterestExpenseExcludingInterestExpenseToRelatedParty	99715000
CY2020	us-gaap	Interest Expense Related Party InterestExpenseRelatedParty	713000
CY2019	us-gaap	Interest Expense Related Party InterestExpenseRelatedParty	1342000
CY2018	us-gaap	Interest Expense Related Party InterestExpenseRelatedParty	1221000
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	4083000
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	4174000
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	3939000
CY2019	ava	Termination Fee Received From Canceled Business Acquisition TerminationFeeReceivedFromCanceledBusinessAcquisition	103000000
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4817000
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	14928000
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1458000
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	136539000
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2393000
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	228137000
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	162658000
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7051000
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CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26060000
CY2020	us-gaap	Profit Loss ProfitLoss	129488000
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CY2018	us-gaap	Profit Loss ProfitLoss	136598000
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-216000
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CY2020	us-gaap	Net Income Loss NetIncomeLoss	129488000
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CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	67962000
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	66205000
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CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	68102000
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CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.91
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CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	523000
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	4119000
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CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	125369000
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CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-216000
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	169000
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	125369000
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	194586000
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CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	4991612000
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CY2020Q4	us-gaap	Goodwill Goodwill	52426000
CY2019Q4	us-gaap	Goodwill Goodwill	52426000
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	750443000
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	670802000
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CY2020Q4	us-gaap	Assets Assets	6402097000
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CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	52000000
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CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	46435000
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	51715000
CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	149831000
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	130979000
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	505879000
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	530713000
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2008534000
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1843768000
CY2020Q4	us-gaap	Due To Related Parties Noncurrent DueToRelatedPartiesNoncurrent	51547000
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CY2020Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	211880000
CY2019Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	212006000
CY2020Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	594712000
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	528513000
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	784820000
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	775436000
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	214999000
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	201189000
CY2020Q4	us-gaap	Liabilities Liabilities	4372371000
CY2019Q4	us-gaap	Liabilities Liabilities	4143172000
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	200000000
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	69238901
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	69238901
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	67176996
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	67176996
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	1286068000
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	1210741000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-14378000
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-10259000
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	758036000
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	738802000
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2029726000
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1939284000
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	6402097000
CY2020	ava	Payments For Proceeds From Derivative Instrument Operating Activities PaymentsForProceedsFromDerivativeInstrumentOperatingActivities	33499000
CY2020	us-gaap	Pension Contributions PensionContributions	22000000
CY2019	us-gaap	Pension Contributions PensionContributions	22000000
CY2018	us-gaap	Pension Contributions PensionContributions	22000000
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	6082456000
CY2020	us-gaap	Profit Loss ProfitLoss	129488000
CY2019	us-gaap	Profit Loss ProfitLoss	196763000
CY2018	us-gaap	Profit Loss ProfitLoss	136598000
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	224223000
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	205994000
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	187318000
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	44964000
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	15098000
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	8570000
CY2020	ava	Power And Natural Gas Cost Amortization Deferrals Net PowerAndNaturalGasCostAmortizationDeferralsNet	-9923000
CY2019	ava	Power And Natural Gas Cost Amortization Deferrals Net PowerAndNaturalGasCostAmortizationDeferralsNet	-45917000
CY2018	ava	Power And Natural Gas Cost Amortization Deferrals Net PowerAndNaturalGasCostAmortizationDeferralsNet	10263000
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	3237000
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2680000
CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2967000
CY2019	us-gaap	Amortization Of Power Contracts Emission Credits AmortizationOfPowerContractsEmissionCredits	1633000
CY2018	us-gaap	Amortization Of Power Contracts Emission Credits AmortizationOfPowerContractsEmissionCredits	2450000
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	5846000
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	11353000
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	5367000
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6970000
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6585000
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6554000
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	33812000
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	36417000
CY2018	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	32017000
CY2020	ava	Other Regulatory Assets And Liabilities Deferred Debits And Credits OtherRegulatoryAssetsAndLiabilitiesDeferredDebitsAndCredits	-10287000
CY2019	ava	Other Regulatory Assets And Liabilities Deferred Debits And Credits OtherRegulatoryAssetsAndLiabilitiesDeferredDebitsAndCredits	-65000
CY2018	ava	Other Regulatory Assets And Liabilities Deferred Debits And Credits OtherRegulatoryAssetsAndLiabilitiesDeferredDebitsAndCredits	-27512000
CY2020	ava	Adjustment In Decoupling Regulatory Deferral AdjustmentInDecouplingRegulatoryDeferral	-2971000
CY2019	ava	Adjustment In Decoupling Regulatory Deferral AdjustmentInDecouplingRegulatoryDeferral	10327000
CY2018	ava	Adjustment In Decoupling Regulatory Deferral AdjustmentInDecouplingRegulatoryDeferral	1288000
CY2020	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	4795000
CY2019	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	7450000
CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	1998000
CY2019	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-13526000
CY2018	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	1114000
CY2019	ava	Payments For Proceeds From Derivative Instrument Operating Activities PaymentsForProceedsFromDerivativeInstrumentOperatingActivities	13325000
CY2018	ava	Payments For Proceeds From Derivative Instrument Operating Activities PaymentsForProceedsFromDerivativeInstrumentOperatingActivities	32174000
CY2018	ava	Proceedsfrom Settlementof Derivative Instruments ProceedsfromSettlementofDerivativeInstruments	5594000
CY2020	us-gaap	Increase Decrease In Accounts And Notes Receivable IncreaseDecreaseInAccountsAndNotesReceivable	10960000
CY2019	us-gaap	Increase Decrease In Accounts And Notes Receivable IncreaseDecreaseInAccountsAndNotesReceivable	4366000
CY2018	us-gaap	Increase Decrease In Accounts And Notes Receivable IncreaseDecreaseInAccountsAndNotesReceivable	-15474000
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	868000
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	6148000
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	5807000
CY2020	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	-1579000
CY2019	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	-63974000
CY2018	us-gaap	Increase Decrease In Deposit Other Assets IncreaseDecreaseInDepositOtherAssets	4128000
CY2020	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	41363000
CY2019	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	8736000
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	180000000
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	374621000
CY2020	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	54800000
CY2019	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	92660000
CY2018	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	277438000
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	72200000
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	64573000
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1207000
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	110254000
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	102772000
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	98046000
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-5307000
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2402000
CY2018	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-2021000
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2401000
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	3657000
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2589000
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-10152000
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	7471000
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-470000
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	15530000
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-1199000
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-370000
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	331004000
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	398212000
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	361885000
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	404306000
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	442510000
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	424350000
CY2020	us-gaap	Payments To Acquire Notes Receivable PaymentsToAcquireNotesReceivable	4393000
CY2019	us-gaap	Payments To Acquire Notes Receivable PaymentsToAcquireNotesReceivable	7303000
CY2018	us-gaap	Payments To Acquire Notes Receivable PaymentsToAcquireNotesReceivable	3555000
CY2020	ava	Payments To Acquire Equity And Property Investments PaymentsToAcquireEquityAndPropertyInvestments	5925000
CY2019	ava	Payments To Acquire Equity And Property Investments PaymentsToAcquireEquityAndPropertyInvestments	13508000
CY2018	ava	Payments To Acquire Equity And Property Investments PaymentsToAcquireEquityAndPropertyInvestments	13283000
CY2020	us-gaap	Proceeds From Sale Of Equity Method Investments ProceedsFromSaleOfEquityMethodInvestments	6786000
CY2019	us-gaap	Proceeds From Sale Of Equity Method Investments ProceedsFromSaleOfEquityMethodInvestments	16407000
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	2905000
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1403000
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-756000
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-410743000
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	165000000
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7916000
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	84039000
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	42539000
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	77031000
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	4300000
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-4760000
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-1516000
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	9896000
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	14656000
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	16172000
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	14196000
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	9896000
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	14656000
CY2020	us-gaap	Interest Paid InterestPaid	97717000
CY2019	us-gaap	Interest Paid InterestPaid	99060000
CY2018	us-gaap	Interest Paid InterestPaid	97437000
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	1901000
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	26764000
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	17801000
CY2020	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	918000
CY2019	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	979000
CY2018	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	3025000
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	32039000
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	25644000
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	31868000
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2029726000
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1939284000
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1773220000
CY2019	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Nonredeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsNonredeemable	-216000
CY2018	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Nonredeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsNonredeemable	169000
CY2019	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	609000
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2029726000
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1939284000
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1774045000
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.62
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.55
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.49
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<p style="margin-top:6pt;margin-bottom:0pt;text-indent:0%;font-weight:bold;font-style:italic;font-family:Times New Roman;font-size:10pt;text-transform:none;font-variant: normal;">Use of Estimates</p> <p style="margin-top:5pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported for assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates include:</p> <div style="align:left;"> <table border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse; width:100%;"> <tr> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:6pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"> </p></td> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:6pt;font-weight:normal;font-style:normal;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"><span style="font-weight:normal;font-style:normal;text-decoration:none;Background-color:#auto;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"/><span style="font-size:10pt;font-family:'Times New Roman'">•</span></p></td> <td valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:6pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"><span style="Background-color:#auto;text-decoration:none;"/><span style="color:#000000;">determining the market value of energy commodity derivative assets and liabilities,</span></p></td></tr></table></div> <div style="align:left;"> <table border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse; width:100%;"> <tr> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"> </p></td> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"><span style="font-weight:normal;font-style:normal;text-decoration:none;Background-color:#auto;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"/><span style="font-size:10pt;font-family:'Times New Roman'">•</span></p></td> <td valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"><span style="Background-color:#auto;text-decoration:none;"/><span style="color:#000000;">pension and other postretirement benefit plan obligations,</span></p></td></tr></table></div> <div style="align:left;"> <table border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse; width:100%;"> <tr> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"> </p></td> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"><span style="font-weight:normal;font-style:normal;text-decoration:none;Background-color:#auto;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"/><span style="font-size:10pt;font-family:'Times New Roman'">•</span></p></td> <td valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"><span style="Background-color:#auto;text-decoration:none;"/><span style="color:#000000;">contingent liabilities,</span></p></td></tr></table></div> <div style="align:left;"> <table border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse; width:100%;"> <tr> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"> </p></td> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"><span style="font-weight:normal;font-style:normal;text-decoration:none;Background-color:#auto;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"/><span style="font-size:10pt;font-family:'Times New Roman'">•</span></p></td> <td valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"><span style="Background-color:#auto;text-decoration:none;"/><span style="color:#000000;">goodwill impairment testing,</span></p></td></tr></table></div> <div style="align:left;"> <table border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse; width:100%;"> <tr> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"> </p></td> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"><span style="font-weight:normal;font-style:normal;text-decoration:none;Background-color:#auto;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"/><span style="font-size:10pt;font-family:'Times New Roman'">•</span></p></td> <td valign="top"> <p style="text-align:left;margin-bottom:0pt;margin-top:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"><span style="Background-color:#auto;text-decoration:none;"/><span style="color:#000000;">recoverability of regulatory assets, and</span></p></td></tr></table></div> <div style="align:left;"> <table border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse; width:100%;"> <tr> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-top:0pt;margin-bottom:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"> </p></td> <td style="width:6.45%;white-space:nowrap" valign="top"> <p style="text-align:left;margin-top:0pt;margin-bottom:0pt;font-weight:normal;font-style:normal;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"><span style="font-weight:normal;font-style:normal;text-decoration:none;Background-color:#auto;color:#auto;font-size:10pt;font-family:'Times New Roman';text-transform:none;font-variant: normal;letter-spacing:0pt;"/><span style="font-size:10pt;font-family:'Times New Roman'">•</span></p></td> <td valign="top"> <p style="text-align:left;margin-top:0pt;margin-bottom:0pt;font-weight:normal;font-style:normal;color:#auto;text-transform:none;font-variant: normal;letter-spacing:0pt;font-family:Times New Roman;font-size:10pt;"><span style="Background-color:#auto;text-decoration:none;"/><span style="color:#000000;">unbilled revenues.</span></p></td></tr></table></div> <p style="margin-top:9pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">Changes in these estimates and assumptions are considered reasonably possible and may have a material effect on the consolidated financial statements and thus actual results could differ from the amounts reported and disclosed herein.</p>
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6970000
CY2020	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	0
CY2019	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	0
CY2018	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	0
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	5846000
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11353000
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	5367000
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1228000
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2384000
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1127000
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	-165000
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	-612000
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	990000
CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	1952000
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	2587000
CY2018	us-gaap	Investment Income Interest InvestmentIncomeInterest	2710000
CY2020	ava	Interest On Regulatory Deferrals InterestOnRegulatoryDeferrals	1222000
CY2019	ava	Interest On Regulatory Deferrals InterestOnRegulatoryDeferrals	1460000
CY2018	ava	Interest On Regulatory Deferrals InterestOnRegulatoryDeferrals	990000
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6585000
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6554000
CY2020	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	6433000
CY2019	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	8899000
CY2018	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	5156000
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	905000
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	14299000
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	-5369000
CY2020	us-gaap	Other Nonoperating Gains Losses OtherNonoperatingGainsLosses	201000
CY2019	us-gaap	Other Nonoperating Gains Losses OtherNonoperatingGainsLosses	-1104000
CY2018	us-gaap	Other Nonoperating Gains Losses OtherNonoperatingGainsLosses	-1187000
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4817000
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	14928000
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1458000
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2419000
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	5233000
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	5132000
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	11280000
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	460000
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	3917000
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	2312000
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	3274000
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	3816000
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	11387000
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2419000
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	5233000
CY2018Q4	us-gaap	Goodwill Goodwill	57672000
CY2019	ava	Goodwill Sold During The Year GoodwillSoldDuringTheYear	-5246000
CY2019Q4	us-gaap	Goodwill Goodwill	52426000
CY2020Q4	us-gaap	Goodwill Goodwill	52426000
CY2020	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0
CY2020	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	<p style="margin-top:9pt;margin-bottom:0pt;text-indent:0%;font-weight:bold;font-style:italic;font-family:Times New Roman;font-size:10pt;text-transform:none;font-variant: normal;">Derivative Assets and Liabilities</p> <p style="margin-top:5pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">Derivatives are recorded as either assets or liabilities on the Consolidated Balance Sheets measured at estimated fair value.</p> <p style="margin-top:9pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">The WUTC and the IPUC issued accounting orders authorizing Avista Corp. to offset energy commodity derivative assets or liabilities with a regulatory asset or liability. This accounting treatment is intended to defer the recognition of mark-to-market gains and losses on energy commodity transactions until the period of delivery. Realized benefits and costs result in adjustments to retail rates through PGAs, the ERM in Washington, the PCA mechanism in Idaho, and periodic general rates cases. The resulting regulatory assets associated with energy commodity derivative instruments have been concluded to be probable of recovery through future rates.</p> <p style="margin-top:9pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">Substantially all forward contracts to purchase or sell power and natural gas are recorded as derivative assets or liabilities at estimated fair value with an offsetting regulatory asset or liability. Contracts that are not considered derivatives are accounted for on the accrual basis until they are settled or realized unless there is a decline in the fair value of the contract that is determined to be other-than-temporary.</p> <p style="margin-top:9pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">For interest rate swap derivatives, Avista Corp. records all mark-to-market gains and losses in each accounting period as assets and liabilities, as well as offsetting regulatory assets and liabilities, such that there is no income statement impact. The interest rate swap derivatives are risk management tools similar to energy commodity derivatives. Upon settlement of interest rate swap derivatives, the regulatory asset or liability is amortized as a component of interest expense over the term of the associated debt. The Company records an offset of interest rate swap derivative assets and liabilities with regulatory assets and liabilities, based on the prior practice of the commissions to provide recovery through the ratemaking process.</p> <p style="margin-top:9pt;margin-bottom:0pt;text-indent:0%;font-family:Times New Roman;font-size:10pt;font-weight:normal;font-style:normal;text-transform:none;font-variant: normal;">The Company has multiple master netting agreements with a variety of entities that allow for cross-commodity netting of derivative agreements with the same counterparty (i.e. power derivatives can be netted with natural gas derivatives). In addition, some master netting agreements allow for the netting of commodity derivatives and interest rate swap derivatives for the same counterparty. The Company does not have any agreements which allow for cross-affiliate netting among multiple affiliated legal entities. The Company nets all derivative instruments when allowed by the agreement for presentation in the Consolidated Balance Sheets.</p>
CY2020Q4	us-gaap	Retained Earnings Appropriated RetainedEarningsAppropriated	47473000
CY2019Q4	us-gaap	Retained Earnings Appropriated RetainedEarningsAppropriated	43151000
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	47338000
CY2020Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	53258000
CY2019Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	47402000
CY2020Q4	us-gaap	Other Inventory OtherInventory	4658000
CY2019Q4	us-gaap	Other Inventory OtherInventory	4875000
CY2020Q4	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	9535000
CY2019Q4	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	14306000
CY2020Q4	us-gaap	Inventory Net InventoryNet	67451000
CY2019Q4	us-gaap	Inventory Net InventoryNet	66583000
CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	4336000
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	4434000
CY2020Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	24411000
CY2019Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	19652000
CY2020Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	49814000
CY2019Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	11047000
CY2020Q4	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	6324000
CY2019Q4	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	5009000
CY2020Q4	us-gaap	Other Assets Current OtherAssetsCurrent	84885000
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	40142000
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	71891000
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	69746000
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	50980000
CY2020Q4	ava	Non Regulated Property NonRegulatedProperty	19508000
CY2019Q4	ava	Non Regulated Property NonRegulatedProperty	27159000
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	59318000
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	51258000
CY2020Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	11547000
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	11547000
CY2020Q4	us-gaap	Notes And Loans Receivable Net Noncurrent NotesAndLoansReceivableNetNoncurrent	14454000
CY2019Q4	us-gaap	Notes And Loans Receivable Net Noncurrent NotesAndLoansReceivableNetNoncurrent	14060000
CY2020Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	9174000
CY2019Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	8948000
CY2020Q4	ava	Assets Held For Sale AssetsHeldForSale	3462000
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	65565000
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	26947000
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	23394000
CY2020Q4	us-gaap	Investments And Other Noncurrent Assets InvestmentsAndOtherNoncurrentAssets	263639000
CY2019Q4	us-gaap	Investments And Other Noncurrent Assets InvestmentsAndOtherNoncurrentAssets	257092000
CY2020Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	45099000
CY2019Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	36965000
CY2020Q4	us-gaap	Energy Marketing Contract Liabilities Current EnergyMarketingContractLiabilitiesCurrent	14008000
CY2019Q4	us-gaap	Energy Marketing Contract Liabilities Current EnergyMarketingContractLiabilitiesCurrent	10928000
CY2020Q4	us-gaap	Accrued Vacation Current AccruedVacationCurrent	26495000
CY2019Q4	us-gaap	Accrued Vacation Current AccruedVacationCurrent	22343000
CY2020Q4	us-gaap	Interest Payable Current InterestPayableCurrent	17083000
CY2019Q4	us-gaap	Interest Payable Current InterestPayableCurrent	16486000
CY2020Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	11987000
CY2019Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	8826000
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	35159000
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	35431000
CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	149831000
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	130979000
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	67716000
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	48815000
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	51750000
CY2020Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	29866000
CY2019Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	30444000
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	17194000
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	20338000
CY2020Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	37427000
CY2019Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	19685000
CY2020Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	13981000
CY2019Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	13407000
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	214999000
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	201189000
CY2020Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	71258000
CY2019Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	63259000
CY2020	ava	Public Utility Operating Expenses Excise Taxes Collected PublicUtilityOperatingExpensesExciseTaxesCollected	59319000
CY2019	ava	Public Utility Operating Expenses Excise Taxes Collected PublicUtilityOperatingExpensesExciseTaxesCollected	59528000
CY2018	ava	Public Utility Operating Expenses Excise Taxes Collected PublicUtilityOperatingExpensesExciseTaxesCollected	58730000
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	23800000
CY2020	us-gaap	Revenues Revenues	1321891000
CY2019	us-gaap	Revenues Revenues	1345622000
CY2018	us-gaap	Revenues Revenues	1396893000
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	4746000
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	4425000
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	1099000
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	988000
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	3641000
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	3641000
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	2662000
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	2795000
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	4612000
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	4375000
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	2662000
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	2795000
CY2020	ava	Total Lease Paymentsin Operating Cash Flows TotalLeasePaymentsinOperatingCashFlows	7274000
CY2019	ava	Total Lease Paymentsin Operating Cash Flows TotalLeasePaymentsinOperatingCashFlows	7170000
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2800000
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2660000
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	71891000
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	69746000
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	4249000
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	4128000
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	67716000
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	65565000
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	71965000
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	69693000
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	47338000
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	50980000
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2935000
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2800000
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	48815000
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	51750000
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	51750000
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	54550000
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P25Y2M12D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P26Y7M6D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P7Y2M19D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P8Y3M7D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0428
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0382
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0462
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0488
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	4779000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	5457000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4799000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	5460000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	4827000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	5456000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4852000
CY2018	us-gaap	Pension Contributions PensionContributions	22000000.0
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	18266000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	5459000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	4865000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	5454000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	96734000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	43661000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	120856000
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	70947000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	48891000
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	19197000
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	71965000
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	51750000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	4372000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	5462000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4375000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	5457000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	4383000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	5460000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4399000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	5456000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	4411000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	5459000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	91654000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	49115000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	113594000
CY2019Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	76409000
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	43901000
CY2019Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	21859000
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	69693000
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	54550000
CY2020Q4	us-gaap	Number Of Foreign Currency Derivatives Held NumberOfForeignCurrencyDerivativesHeld	22
CY2019Q4	us-gaap	Number Of Foreign Currency Derivatives Held NumberOfForeignCurrencyDerivativesHeld	20
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	17194000
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	20338000
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	24702000
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	83280000
CY2020Q4	us-gaap	Derivative Fair Value Amount Offset Against Collateral Net DerivativeFairValueAmountOffsetAgainstCollateralNet	8666000
CY2020Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	-49912000
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	43222000
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	82203000
CY2019Q4	us-gaap	Derivative Fair Value Amount Offset Against Collateral Net DerivativeFairValueAmountOffsetAgainstCollateralNet	10148000
CY2019Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	-28833000
CY2020Q4	us-gaap	Jointly Owned Utility Plant Proportionate Ownership Share JointlyOwnedUtilityPlantProportionateOwnershipShare	0.15
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	6809797000
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	6462993000
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	175767000
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	164941000
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	6985564000
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	6627934000
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1993952000
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1830927000
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	4991612000
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	4797007000
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	6985564000
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	6627934000
CY2020Q4	ava	Property Plant And Equipment Total PropertyPlantAndEquipmentTotal	7001958000
CY2019Q4	ava	Property Plant And Equipment Total PropertyPlantAndEquipmentTotal	6656129000
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	20338000
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	18266000
CY2017Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	17482000
CY2020	ava	Asset Retirement Obligation Increase Decrease In Liabilities Incurred AssetRetirementObligationIncreaseDecreaseInLiabilitiesIncurred	-2315000
CY2019	ava	Asset Retirement Obligation Increase Decrease In Liabilities Incurred AssetRetirementObligationIncreaseDecreaseInLiabilitiesIncurred	2699000
CY2020	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	1645000
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	1503000
CY2018	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	66000
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	816000
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	876000
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	850000
CY2020	us-gaap	Pension Contributions PensionContributions	22000000.0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	ava	Percentage Of Service Related Net Periodic Benefit Costs Capitalized To Utility Property PercentageOfServiceRelatedNetPeriodicBenefitCostsCapitalizedToUtilityProperty	0.40
CY2020	ava	Percentage Of Service Related Net Periodic Benefit Costs Recorded To Operating Expenses PercentageOfServiceRelatedNetPeriodicBenefitCostsRecordedToOperatingExpenses	0.60
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	11742000
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	10412000
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	10243000
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-37913000
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16276000
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	17490000
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	44964000
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	15098000
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	8570000
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7051000
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26060000
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	28673000
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	47909000
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	34158000
CY2020	ava	Tax Effect Of Regulatory Treatment Of Utility Plant Differences TaxEffectOfRegulatoryTreatmentOfUtilityPlantDifferences	-12893000
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	265425000
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	666639000
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	581387000
CY2020	ava	Tax Effect Of Regulatory Treatment Of Utility Plant Differences Percent TaxEffectOfRegulatoryTreatmentOfUtilityPlantDifferencesPercent	-0.094
CY2019	ava	Tax Effect Of Regulatory Treatment Of Utility Plant Differences TaxEffectOfRegulatoryTreatmentOfUtilityPlantDifferences	-9967000
CY2019	ava	Tax Effect Of Regulatory Treatment Of Utility Plant Differences Percent TaxEffectOfRegulatoryTreatmentOfUtilityPlantDifferencesPercent	-0.043
CY2018	ava	Tax Effect Of Regulatory Treatment Of Utility Plant Differences TaxEffectOfRegulatoryTreatmentOfUtilityPlantDifferences	-8153000
CY2018	ava	Tax Effect Of Regulatory Treatment Of Utility Plant Differences Percent TaxEffectOfRegulatoryTreatmentOfUtilityPlantDifferencesPercent	-0.050
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	814000
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.006
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1465000
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.006
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1191000
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.007
CY2019	ava	Income Tax Reconciliation Nondeductible Expense Acquisition Costs Amount IncomeTaxReconciliationNondeductibleExpenseAcquisitionCostsAmount	-1712000
CY2019	ava	Income Tax Reconciliation Nondeductible Expense Acquisition Costs Percent IncomeTaxReconciliationNondeductibleExpenseAcquisitionCostsPercent	-0.007
CY2018	ava	Income Tax Reconciliation Nondeductible Expense Acquisition Costs Amount IncomeTaxReconciliationNondeductibleExpenseAcquisitionCostsAmount	329000
CY2018	ava	Income Tax Reconciliation Nondeductible Expense Acquisition Costs Percent IncomeTaxReconciliationNondeductibleExpenseAcquisitionCostsPercent	0.002
CY2020	ava	Effective Income Tax Rate Reconciliation Excess Deferred Income Tax Reversal Amount EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxReversalAmount	8476000
CY2020	ava	Effective Income Tax Rate Reconciliation Excess Deferred Income Tax Reversal Percent EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxReversalPercent	-0.062
CY2019	ava	Effective Income Tax Rate Reconciliation Excess Deferred Income Tax Reversal Amount EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxReversalAmount	5690000
CY2019	ava	Effective Income Tax Rate Reconciliation Excess Deferred Income Tax Reversal Percent EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxReversalPercent	-0.025
CY2019	us-gaap	Income Tax Reconciliation Disposition Of Business IncomeTaxReconciliationDispositionOfBusiness	-1272000
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	-0.006
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2020	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	-1189000
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.009
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	122000
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.001
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	641000
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.003
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1465000
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.009
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7051000
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.052
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	31374000
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.138
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26060000
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.160
CY2020Q4	ava	Deferred Tax Assets Regulatory Liabilities DeferredTaxAssetsRegulatoryLiabilities	179871000
CY2019Q4	ava	Deferred Tax Assets Regulatory Liabilities DeferredTaxAssetsRegulatoryLiabilities	181455000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	57516000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	22331000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	37501000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	41648000
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	42641000
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	36542000
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	317529000
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	281976000
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	10021000
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	16551000
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	307508000
CY2020Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssets	232697000
CY2019Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssets	210231000
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2008534000
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount DebtInstrumentUnamortizedDiscount	710000
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2884000
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2320000
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	902220000
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	793938000
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	594712000
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	528513000
CY2020	ava	Utility Power Resources UtilityPowerResources	324297000
CY2019	ava	Utility Power Resources UtilityPowerResources	376769000
CY2018	ava	Utility Power Resources UtilityPowerResources	357656000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	249589000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	229944000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	216035000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	192819000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary	190360000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	1090589000
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	2169336000
CY2020	us-gaap	Long Term Contract For Purchase Of Electric Power Amount Of Long Term Debt Or Lease Obligation Outstanding LongTermContractForPurchaseOfElectricPowerAmountOfLongTermDebtOrLeaseObligationOutstanding	63700000
CY2020Q4	us-gaap	Secured Debt SecuredDebt	2092200000
CY2019Q4	us-gaap	Secured Debt SecuredDebt	1979200000
CY2020Q4	ava	Securedand Unsecured Debt SecuredandUnsecuredDebt	2107200000
CY2019Q4	ava	Securedand Unsecured Debt SecuredandUnsecuredDebt	1994200000
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount DebtInstrumentUnamortizedDiscount	788000
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	14256000
CY2019Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	13944000
CY2020Q4	ava	Long Term Debt Before Current Portion And Bonds Held By Company LongTermDebtBeforeCurrentPortionAndBondsHeldByCompany	2092234000
CY2019Q4	ava	Long Term Debt Before Current Portion And Bonds Held By Company LongTermDebtBeforeCurrentPortionAndBondsHeldByCompany	1979468000
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	52000000
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.91
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.98
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1843768000
CY2020	ava	Payments For Proceeds From Derivative Instrument Operating Activities PaymentsForProceedsFromDerivativeInstrumentOperatingActivities	33500000
CY1997Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	51500000
CY1997	ava	Proceeds From The Issuanceof Common Trust Securities ProceedsFromTheIssuanceofCommonTrustSecurities	1500000
CY2000	us-gaap	Payments For Repurchase Of Trust Preferred Securities PaymentsForRepurchaseOfTrustPreferredSecurities	10000000.0
CY2020Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	51500000
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	65946000
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0
CY2020Q4	ava	Amount Available For Dividend Distribution Without Affecting Covenants AmountAvailableForDividendDistributionWithoutAffectingCovenants	311800000
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	10000000
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0
CY2019Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	72200000
CY2020Q4	ava	Accumulated Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Tax AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossTax	3822000
CY2019Q4	ava	Accumulated Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Tax AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossTax	2727000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-14378000
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-10259000
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	129488000
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	196979000
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	136429000
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	67962000
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	66205000
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	65673000
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	140000
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	124000
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	273000
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	68102000
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	66329000
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.08
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.90
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.97
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.07
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0
CY2019Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	21851000
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	670802000
CY2020Q4	ava	Regulatory Liability Earning Return RegulatoryLiabilityEarningReturn	785088000
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	196979000
CY2018	ava	Other Operating Expenses OtherOperatingExpenses	350073000
CY2020Q4	us-gaap	Amount Of Regulatory Costs Not Yet Approved AmountOfRegulatoryCostsNotYetApproved	95414000
CY2020Q4	ava	Remaining Amounts Of Regulatory Liabilities For Which No Interest During Recovery Period Is Provided RemainingAmountsOfRegulatoryLiabilitiesForWhichNoInterestDuringRecoveryPeriodIsProvided	35218000
CY2020Q4	ava	Regulatory Asset Earning Return RegulatoryAssetEarningReturn	448712000
CY2020Q4	us-gaap	Remaining Amounts Of Regulatory Assets For Which No Return On Investment During Recovery Period Is Provided RemainingAmountsOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided	219990000
CY2020Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	13673000
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	750443000
CY2018	ava	Depreciation And Amortization Expense DepreciationAndAmortizationExpense	183676000
CY2019	ava	Payments To Acquire Property Plant And Equipment Excludes Other Business Expenditure PaymentsToAcquirePropertyPlantAndEquipmentExcludesOtherBusinessExpenditure	443345000
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	31374000
CY2020Q4	ava	Pending Regulatory Treatment Liability PendingRegulatoryTreatmentLiability	10949000
CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	46435000
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	784820000
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	51715000
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	775436000
CY2016Q1	ava	Number Of Electric Meters To Be Replaced NumberOfElectricMetersToBeReplaced	253000
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020	ava	Threshold Limit Of Deadband And Sharing Bands For Future Surcharge Or Rebate To Customer ThresholdLimitOfDeadbandAndSharingBandsForFutureSurchargeOrRebateToCustomer	4000000.0
CY2020	ava	Company Shareof Benefit Expense Under Washington Energy Recovery Mechanism CompanyShareofBenefitExpenseUnderWashingtonEnergyRecoveryMechanism	6200000
CY2019	ava	Company Shareof Benefit Expense Under Washington Energy Recovery Mechanism CompanyShareofBenefitExpenseUnderWashingtonEnergyRecoveryMechanism	4400000
CY2020Q4	ava	Thresholdto Return Washington Energy Recovery Mechanism Dollarsto Customers ThresholdtoReturnWashingtonEnergyRecoveryMechanismDollarstoCustomers	30000000
CY2020Q4	ava	Thresholdto Return Washington Energy Recovery Mechanism Dollarsto Customers ThresholdtoReturnWashingtonEnergyRecoveryMechanismDollarstoCustomers	30000000
CY2020Q4	us-gaap	Deferred Gas Cost DeferredGasCost	1400000
CY2019Q4	us-gaap	Refundable Gas Costs RefundableGasCosts	3200000
CY2020	us-gaap	Revenues Revenues	1321891000
CY2020	ava	Utilities Operating Expense Deferrals For Products And Services UtilitiesOperatingExpenseDeferralsForProductsAndServices	398509000
CY2020	ava	Other Operating Expenses OtherOperatingExpenses	359958000
CY2020	ava	Depreciation And Amortization Expense DepreciationAndAmortizationExpense	224223000
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	232700000
CY2020	ava	Interest Expense Including Affiliated Trusts InterestExpenseIncludingAffiliatedTrusts	105061000
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7051000
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	129488000
CY2020	ava	Payments To Acquire Property Plant And Equipment Excludes Other Business Expenditure PaymentsToAcquirePropertyPlantAndEquipmentExcludesOtherBusinessExpenditure	405674000
CY2019	us-gaap	Revenues Revenues	1345622000
CY2019	ava	Utilities Operating Expense Deferrals For Products And Services UtilitiesOperatingExpenseDeferralsForProductsAndServices	439817000
CY2019	ava	Other Operating Expenses OtherOperatingExpenses	383770000
CY2019	ava	Depreciation And Amortization Expense DepreciationAndAmortizationExpense	205994000
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	210389000
CY2019	ava	Interest Expense Including Affiliated Trusts InterestExpenseIncludingAffiliatedTrusts	104354000
CY2018	us-gaap	Revenues Revenues	1396893000
CY2018	ava	Utilities Operating Expense Deferrals For Products And Services UtilitiesOperatingExpenseDeferralsForProductsAndServices	494736000
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	261113000
CY2018	ava	Interest Expense Including Affiliated Trusts InterestExpenseIncludingAffiliatedTrusts	100936000
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26060000
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	136429000
CY2020Q4	us-gaap	Assets Assets	6402097000
CY2019Q4	us-gaap	Assets Assets	6082456000
CY2018Q4	us-gaap	Assets Assets	5782576000
CY2018	ava	Payments To Acquire Property Plant And Equipment Excludes Other Business Expenditure PaymentsToAcquirePropertyPlantAndEquipmentExcludesOtherBusinessExpenditure	425241000
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	19700000

Files In Submission

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$AVA
AVISTA CORP Stock $ava

2019 Q4 Form 10-K Financial Statement

#000156459021007774 Filed on February 24, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AVA AVISTA CORP Stock $ava

2019 Q4 Form 10-K Financial Statement

#000156459021007774 Filed on February 24, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AVA
AVISTA CORP Stock $ava