$NWN
Northwest Natural Holding Co Stock $nwn

$nwn Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000173399821000006 Filed on February 26, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue	$247.3M	$226.7M	$706.1M
YoY Change	9.07%	-5.0%	-6.48%
Cost Of Revenue	$110.8M	$112.2M	$293.0M
YoY Change	-1.25%	21.82%	-7.57%
Gross Profit	$136.5M	$114.5M	$413.1M
YoY Change	19.21%	-21.84%	-5.68%
Gross Profit Margin	55.2%	50.51%	58.5%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$24.20M	$21.70M	$85.20M
YoY Change	11.52%	26.16%	5.06%
% of Gross Profit	17.73%	18.95%	20.62%
Operating Expenses	$84.20M	$75.20M	$574.0M
YoY Change	11.97%	-3.34%	-4.99%
Operating Profit	$52.30M	$39.30M	$132.2M
YoY Change	33.08%	-42.79%	-12.42%
Interest Expense	-$2.200M	$13.00M	-$37.06M
YoY Change	-116.92%	-172.22%	-1.24%
% of Operating Profit	-4.21%	33.08%	-28.04%
Other Income/Expense, Net	-$4.100M	-$2.500M	-$3.601M
YoY Change	64.0%	-933.33%	1120.68%
Pretax Income	$46.00M	$49.80M	$91.50M
YoY Change	-7.63%	-2.35%	-19.08%
Income Tax	$7.700M	$13.00M	$24.19M
% Of Pretax Income	16.74%	26.1%	26.44%
Net Earnings	$36.74M	$35.82M	$64.57M
YoY Change	2.56%	-139.73%	-216.08%
Net Earnings / Revenue	14.86%	15.8%	9.14%
Basic Earnings Per Share	$1.21	$1.24	$2.24
Diluted Earnings Per Share	$1.20	$1.24	$2.24
COMMON SHARES
Basic Shares Outstanding	30.45M shares	28.85M shares	28.80M shares
Diluted Shares Outstanding	30.52M shares	28.94M shares	28.87M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments	$9.600M	$12.60M	$12.60M
YoY Change	-23.81%	260.0%	260.0%
Cash & Equivalents	$9.648M	$12.63M	$12.60M
Short-Term Investments
Other Short-Term Assets	$38.00M	$28.47M	$150.5M
YoY Change	33.48%	14.12%	9.14%
Inventory	$59.30M	$60.80M	$60.80M
Prepaid Expenses
Receivables	$66.50M	$66.00M	$66.00M
Other Receivables	$200.0K	$6.000M	$6.000M
Total Short-Term Assets	$293.7M	$295.9M	$295.9M
YoY Change	-0.75%	9.63%	9.63%
LONG-TERM ASSETS
Property, Plant & Equipment	$2.439B	$2.421B	$2.421B
YoY Change	0.72%	7.9%	7.89%
Goodwill	$49.90M	$9.000M
YoY Change	454.44%
Intangibles
YoY Change
Long-Term Investments	$13.47M	$13.57M	$63.60M
YoY Change	-0.73%	-0.72%	-4.22%
Other Assets	$38.46M	$14.15M	$452.9M
YoY Change	171.85%	117.51%	-1.39%
Total Long-Term Assets	$3.135B	$2.947B	$2.947B
YoY Change	6.38%	6.39%	6.39%
TOTAL ASSETS
Total Short-Term Assets	$293.7M	$295.9M	$295.9M
Total Long-Term Assets	$3.135B	$2.947B	$2.947B
Total Assets	$3.428B	$3.243B	$3.243B
YoY Change	5.73%	6.68%	6.68%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$113.4M	$115.9M	$115.9M
YoY Change	-2.16%	4.37%	4.41%
Accrued Expenses	$9.600M	$7.300M	$7.300M
YoY Change	31.51%	7.35%	7.35%
Deferred Revenue
YoY Change
Short-Term Debt	$149.1M	$217.6M	$217.6M
YoY Change	-31.48%	301.48%	301.48%
Long-Term Debt Due	$75.11M	$29.99M	$30.00M
YoY Change	150.46%	-68.99%	-68.98%
Total Short-Term Liabilities	$482.2M	$509.1M	$509.1M
YoY Change	-5.29%	33.32%	33.31%
LONG-TERM LIABILITIES
Long-Term Debt	$806.0M	$706.2M	$706.2M
YoY Change	14.12%	3.38%	3.37%
Other Long-Term Liabilities	$123.4M	$147.8M	$984.2M
YoY Change	-16.5%	9.22%	2.37%
Total Long-Term Liabilities	$929.3M	$854.0M	$1.690B
YoY Change	8.82%	4.34%	2.78%
TOTAL LIABILITIES
Total Short-Term Liabilities	$482.2M	$509.1M	$509.1M
Total Long-Term Liabilities	$929.3M	$854.0M	$1.690B
Total Liabilities	$1.412B	$1.363B	$2.480B
YoY Change	3.55%	13.56%	7.97%
SHAREHOLDERS EQUITY
Retained Earnings	$318.5M	$312.2M
YoY Change	2.01%	3.25%
Common Stock	$558.3M	$457.6M
YoY Change	21.99%	1.95%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$866.0M	$762.6M	$762.6M
YoY Change
Total Liabilities & Shareholders Equity	$3.428B	$3.243B	$3.243B
YoY Change	5.73%	6.68%	6.68%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	$36.74M	$35.82M	$64.57M
YoY Change	2.56%	-139.73%	-216.08%
Depreciation, Depletion And Amortization	$24.20M	$21.70M	$85.20M
YoY Change	11.52%	26.16%	5.06%
Cash From Operating Activities	$30.00M	$10.30M	$168.8M
YoY Change	191.26%	-25.36%	-18.35%
INVESTING ACTIVITIES
Capital Expenditures	-$70.50M	-$55.80M	$214.6M
YoY Change	26.34%	-17.82%	0.61%
Acquisitions			$873.0K
YoY Change
Other Investing Activities	-$8.000M	-$500.0K	-$1.421M
YoY Change	1500.0%	-266.67%	-346.27%
Cash From Investing Activities	-$78.50M	-$56.40M	-$217.5M
YoY Change	39.18%	-16.57%	1.53%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$0.00
YoY Change			-100.0%
Debt Paid & Issued, Net			$97.00M
YoY Change			142.5%
Cash From Financing Activities	47.60M	28.80M	$57.84M
YoY Change	65.28%	-30.43%	679.66%
NET CHANGE
Cash From Operating Activities	30.00M	10.30M	$168.8M
Cash From Investing Activities	-78.50M	-56.40M	-$217.5M
Cash From Financing Activities	47.60M	28.80M	$57.84M
Net Change In Cash	-900.0K	-17.30M	$9.161M
YoY Change	-94.8%	39.52%	-18795.92%
FREE CASH FLOW
Cash From Operating Activities	$30.00M	$10.30M	$168.8M
Capital Expenditures	-$70.50M	-$55.80M	$214.6M
Free Cash Flow	$100.5M	$66.10M	-$45.87M
YoY Change	52.04%	-19.09%	592.72%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
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CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P0Y
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	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
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CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Registrant Name EntityRegistrantName	NORTHWEST NATURAL HOLDING COMPANY
CY2020	dei	Entity File Number EntityFileNumber	1-38681
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	OR
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	82-4710680
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	250 S.W. Taylor Street
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Portland
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	OR
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	97204
CY2020	dei	City Area Code CityAreaCode	(503)
CY2020	dei	Local Phone Number LocalPhoneNumber	226-4211
CY2020	dei	Security12b Title Security12bTitle	Common Stock
CY2020	dei	Trading Symbol TradingSymbol	NWN
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 Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
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CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1037847000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2654770000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2438899000	USD
CY2020Q4	us-gaap	Inventory Gas In Storage Underground Noncurrent InventoryGasInStorageUndergroundNoncurrent	34484000	USD
CY2019Q4	us-gaap	Inventory Gas In Storage Underground Noncurrent InventoryGasInStorageUndergroundNoncurrent	48394000	USD
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	348927000	USD
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	343146000	USD
CY2020Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	6135000	USD
CY2019Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	3337000	USD
CY2020Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	49259000	USD
CY2019Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	63333000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	77446000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	2950000	USD
CY2020Q4	us-gaap	Net Investment In Lease Noncurrent NetInvestmentInLeaseNoncurrent	143759000	USD
CY2019Q4	us-gaap	Net Investment In Lease Noncurrent NetInvestmentInLeaseNoncurrent	146310000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	69225000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	49929000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	49129000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	38464000	USD
CY2020Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	3433134000	USD
CY2019Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	3134762000	USD
CY2020Q4	us-gaap	Assets Assets	3756379000	USD
CY2019Q4	us-gaap	Assets Assets	3428454000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	304525000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	149100000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	95344000	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	75109000	USD
CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	97966000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	113370000	USD
CY2020Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	13812000	USD
CY2019Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	11971000	USD
CY2020Q4	us-gaap	Interest Payable Current InterestPayableCurrent	7441000	USD
CY2019Q4	us-gaap	Interest Payable Current InterestPayableCurrent	7451000	USD
CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	50362000	USD
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	44657000	USD
CY2020Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	4198000	USD
CY2019Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	2000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	1105000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	2101000	USD
CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	52330000	USD
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	62705000	USD
CY2020Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	0	USD
CY2019Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	13709000	USD
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	627083000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	482173000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	860081000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	805955000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	319292000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	295643000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	639663000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	625717000	USD
CY2020Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	217287000	USD
CY2019Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	228129000	USD
CY2020Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	2852000	USD
CY2019Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	609000	USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2019Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	80621000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	841000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	120767000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	123388000	USD
CY2020Q4	us-gaap	Deferred Credits And Other Liabilities Noncurrent DeferredCreditsAndOtherLiabilitiesNoncurrent	1380482000	USD
CY2019Q4	us-gaap	Deferred Credits And Other Liabilities Noncurrent DeferredCreditsAndOtherLiabilitiesNoncurrent	1274327000	USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	30589000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	30589000	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	30472000	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	30472000	shares
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	565112000	USD
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	558282000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	336523000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	318450000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-12902000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-10733000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	888733000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	865999000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3756379000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3428454000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	742776000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	65819000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.89
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	54736000	USD
CY2018	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	3020000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5175000	USD
CY2018	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	7945000	USD
CY2018	us-gaap	Business Combination Consideration Transferred Equity Interests Issued And Issuable BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable	8525000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	762634000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	59556000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.90
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	56833000	USD
CY2019	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	2601000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5085000	USD
CY2019	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	92956000	USD
CY2019	nwn	Stranded Deferred Tax Remeasurement Benefit StrandedDeferredTaxRemeasurementBenefit	0	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	865999000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	74612000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.91
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	58708000	USD
CY2020	us-gaap	Stock Granted During Period Value Sharebased Compensation StockGrantedDuringPeriodValueSharebasedCompensation	4361000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2469000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	888733000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	76781000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	61735000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	64569000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	103683000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	91496000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	85156000	USD
CY2020	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	17779000	USD
CY2019	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	19172000	USD
CY2018	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	16684000	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	18667000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	6317000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	14356000	USD
CY2020	us-gaap	Pension Expense PensionExpense	18370000	USD
CY2019	us-gaap	Pension Expense PensionExpense	16497000	USD
CY2018	us-gaap	Pension Expense PensionExpense	8108000	USD
CY2020	us-gaap	Pension Contributions PensionContributions	28980000	USD
CY2019	us-gaap	Pension Contributions PensionContributions	10970000	USD
CY2018	us-gaap	Pension Contributions PensionContributions	15540000	USD
CY2020	us-gaap	Other Increase Decrease In Environmental Liabilities OtherIncreaseDecreaseInEnvironmentalLiabilities	-27871000	USD
CY2019	us-gaap	Other Increase Decrease In Environmental Liabilities OtherIncreaseDecreaseInEnvironmentalLiabilities	-16226000	USD
CY2018	us-gaap	Other Increase Decrease In Environmental Liabilities OtherIncreaseDecreaseInEnvironmentalLiabilities	-14528000	USD
CY2020	us-gaap	Environmental Remediation Expense EnvironmentalRemediationExpense	9691000	USD
CY2019	us-gaap	Environmental Remediation Expense EnvironmentalRemediationExpense	12337000	USD
CY2018	us-gaap	Environmental Remediation Expense EnvironmentalRemediationExpense	11127000	USD
CY2020	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	0	USD
CY2019	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	853000	USD
CY2018	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	7929000	USD
CY2020	us-gaap	Pension Expense Reversal Of Expense Noncash PensionExpenseReversalOfExpenseNoncash	0	USD
CY2019	us-gaap	Pension Expense Reversal Of Expense Noncash PensionExpenseReversalOfExpenseNoncash	10500000	USD
CY2018	us-gaap	Pension Expense Reversal Of Expense Noncash PensionExpenseReversalOfExpenseNoncash	0	USD
CY2020	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	5902000	USD
CY2019	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	0	USD
CY2018	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	0	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	6942000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-13907000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-1596000	USD
CY2020	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	16799000	USD
CY2019	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-5844000	USD
CY2018	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-181000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-1262000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	5969000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-3207000	USD
CY2020	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	-10710000	USD
CY2019	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	4528000	USD
CY2018	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	-16904000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-15910000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-16485000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	16792000	USD
CY2020	us-gaap	Increase Decrease In Deferred Gas Cost IncreaseDecreaseInDeferredGasCost	-17590000	USD
CY2019	us-gaap	Increase Decrease In Deferred Gas Cost IncreaseDecreaseInDeferredGasCost	23471000	USD
CY2018	us-gaap	Increase Decrease In Deferred Gas Cost IncreaseDecreaseInDeferredGasCost	14395000	USD
CY2020	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-2884000	USD
CY2019	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-18661000	USD
CY2018	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-4497000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	12467000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	4140000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	3419000	USD
CY2020	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	1894000	USD
CY2019	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	712000	USD
CY2018	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	-645000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	143020000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	185298000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	168771000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	273016000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	223471000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	214636000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	38263000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	56786000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	873000	USD
CY2020	us-gaap	Operating Lease Payments Use OperatingLeasePaymentsUse	7878000	USD
CY2019	us-gaap	Operating Lease Payments Use OperatingLeasePaymentsUse	18812000	USD
CY2018	us-gaap	Operating Lease Payments Use OperatingLeasePaymentsUse	4415000	USD
CY2020	us-gaap	Proceeds From Sale Of Land Held For Use ProceedsFromSaleOfLandHeldForUse	8149000	USD
CY2019	us-gaap	Proceeds From Sale Of Land Held For Use ProceedsFromSaleOfLandHeldForUse	659000	USD
CY2018	us-gaap	Proceeds From Sale Of Land Held For Use ProceedsFromSaleOfLandHeldForUse	477000	USD
CY2020	us-gaap	Proceeds From Sale Of Equity Method Investments ProceedsFromSaleOfEquityMethodInvestments	7000000	USD
CY2019	us-gaap	Proceeds From Sale Of Equity Method Investments ProceedsFromSaleOfEquityMethodInvestments	0	USD
CY2018	us-gaap	Proceeds From Sale Of Equity Method Investments ProceedsFromSaleOfEquityMethodInvestments	0	USD
CY2020	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	12500000	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1654000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	3544000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1421000	USD
CY2020	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-4423000	USD
CY2019	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-1827000	USD
CY2018	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	573000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-294277000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-303781000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-217453000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	68000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2015000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	1546000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	92956000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	150000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	175000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	50000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	75000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	30000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	97000000	USD
CY2020	us-gaap	Proceeds From Debt Maturing In More Than Three Months ProceedsFromDebtMaturingInMoreThanThreeMonths	150000000	USD
CY2019	us-gaap	Proceeds From Debt Maturing In More Than Three Months ProceedsFromDebtMaturingInMoreThanThreeMonths	0	USD
CY2018	us-gaap	Proceeds From Debt Maturing In More Than Three Months ProceedsFromDebtMaturingInMoreThanThreeMonths	0	USD
CY2020	us-gaap	Repayments Of Debt Maturing In More Than Three Months RepaymentsOfDebtMaturingInMoreThanThreeMonths	150000000	USD
CY2019	us-gaap	Repayments Of Debt Maturing In More Than Three Months RepaymentsOfDebtMaturingInMoreThanThreeMonths	0	USD
CY2018	us-gaap	Repayments Of Debt Maturing In More Than Three Months RepaymentsOfDebtMaturingInMoreThanThreeMonths	0	USD
CY2020	nwn	Proceeds From Issuances Of Commercial Paper Maturities Greater Than90 Days ProceedsFromIssuancesOfCommercialPaperMaturitiesGreaterThan90Days	195025000	USD
CY2019	nwn	Proceeds From Issuances Of Commercial Paper Maturities Greater Than90 Days ProceedsFromIssuancesOfCommercialPaperMaturitiesGreaterThan90Days	0	USD
CY2018	nwn	Proceeds From Issuances Of Commercial Paper Maturities Greater Than90 Days ProceedsFromIssuancesOfCommercialPaperMaturitiesGreaterThan90Days	0	USD
CY2020	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-39600000	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-68520000	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	163274000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	55420000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	53339000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	51311000	USD
CY2020	nwn	Paymentsforthe Repurchaseof Common Stock Relatedto Acquisitions PaymentsfortheRepurchaseofCommonStockRelatedtoAcquisitions	0	USD
CY2019	nwn	Paymentsforthe Repurchaseof Common Stock Relatedto Acquisitions PaymentsfortheRepurchaseofCommonStockRelatedtoAcquisitions	0	USD
CY2018	nwn	Paymentsforthe Repurchaseof Common Stock Relatedto Acquisitions PaymentsfortheRepurchaseofCommonStockRelatedtoAcquisitions	7951000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-3296000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2614000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-715000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	171777000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	115498000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	57843000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	20520000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-2985000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	9161000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	9648000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	12633000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	3472000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	30168000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	9648000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	12633000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	42651000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	41231000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	35324000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	13644000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-96000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	27370000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9.5pt;font-weight:700;line-height:120%;text-decoration:underline">Use of Estimates</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> </span></div><div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with generally accepted accounting principles in the United States of America (U.S. GAAP) requires management to make estimates and assumptions that affect reported amounts in the consolidated financial statements and accompanying notes. Actual amounts could differ from those estimates, and changes would most likely be reported in future periods. Management believes the estimates and assumptions used are reasonable</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">.</span></div>
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	348927000	USD
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	343146000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	639663000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	625717000	USD
CY2020	nwn	Weighted Average Depreciation Rates Transmission Distribution WeightedAverageDepreciationRatesTransmissionDistribution	0.026	number
CY2020	nwn	Weighted Average Depreciation Rates Utility Storage WeightedAverageDepreciationRatesUtilityStorage	0.020	number
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	70273000	USD
CY2020	nwn	Weighted Average Depreciation Rates General Plant WeightedAverageDepreciationRatesGeneralPlant	0.067	number
CY2020	nwn	Weighted Average Depreciation Rates Intangible Other WeightedAverageDepreciationRatesIntangibleOther	0.051	number
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.019	number
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.039	number
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.052	number
CY2020Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	57900000	USD
CY2019Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	56200000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	65311000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	673000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	3223000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	677000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	3219000	USD
CY2020Q4	us-gaap	Inventory Raw Materials And Supplies Net Of Reserves InventoryRawMaterialsAndSuppliesNetOfReserves	18000000.0	USD
CY2019Q4	us-gaap	Inventory Raw Materials And Supplies Net Of Reserves InventoryRawMaterialsAndSuppliesNetOfReserves	16500000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	69200000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	49900000	USD
CY2020Q4	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	67311000	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	6508000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-3576000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-2742000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	76781000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	61735000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	64569000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	30541000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	29786000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	28803000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	58000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	73000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	70000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	30599000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	29859000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	28873000	shares
CY2020	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.30
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.19
CY2018	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.34
CY2020	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.30
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.19
CY2018	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.33
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.51
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.07
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.24
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.51
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.07
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.24
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2000	shares
CY2019Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	15100000	USD
CY2018Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	13300000	USD
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	1437500	shares
CY2019Q2	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	67.00
	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	93000000.0	USD
CY2020	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	744366000	USD
CY2020	us-gaap	Revenues Revenues	773679000	USD
CY2019	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	755987000	USD
CY2019	us-gaap	Revenues Revenues	746372000	USD
CY2020Q4	us-gaap	Lessor Sales Type Lease Term Of Contract1 LessorSalesTypeLeaseTermOfContract1	P30Y
CY2020Q4	us-gaap	Lessor Sales Type Lease Renewal Term1 LessorSalesTypeLeaseRenewalTerm1	P50Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	88400000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	19000000.0	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	19400000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	17800000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	14000000.0	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	18200000	USD
CY2020Q4	us-gaap	Lessor Sales Type Lease Term Of Contract1 LessorSalesTypeLeaseTermOfContract1	P30Y
CY2020Q4	us-gaap	Lessor Sales Type Lease Renewal Term1 LessorSalesTypeLeaseRenewalTerm1	P50Y
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	88000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	171000	USD
CY2020	us-gaap	Sales Type Lease Lease Income SalesTypeLeaseLeaseIncome	18355000	USD
CY2019	us-gaap	Sales Type Lease Lease Income SalesTypeLeaseLeaseIncome	11198000	USD
CY2020	us-gaap	Lease Income LeaseIncome	18443000	USD
CY2019	us-gaap	Lease Income LeaseIncome	11369000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Next Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths	59000	USD
CY2020Q4	nwn	Lease Paymentstobe Received Nexttwelvemonths LeasePaymentstobeReceivedNexttwelvemonths	17577000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	55000	USD
CY2020Q4	nwn	Lease Paymentstobe Received Two Years LeasePaymentstobeReceivedTwoYears	17081000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	47000	USD
CY2020Q4	nwn	Lease Paymentstobe Received Three Years LeasePaymentstobeReceivedThreeYears	16604000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	47000	USD
CY2020Q4	nwn	Lease Paymentstobe Received Four Years LeasePaymentstobeReceivedFourYears	15914000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	43000	USD
CY2020Q4	nwn	Lease Paymentstobe Received Five Years LeasePaymentstobeReceivedFiveYears	15349000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Thereafter LessorOperatingLeasePaymentsToBeReceivedThereafter	52000	USD
CY2020Q4	nwn	Lease Paymentstobe Received Thereafter LeasePaymentstobeReceivedThereafter	251773000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	303000	USD
CY2020Q4	nwn	Lease Paymentstobe Received LeasePaymentstobeReceived	334298000	USD
CY2020Q4	us-gaap	Residual Value Of Leased Asset ResidualValueOfLeasedAsset	4300000	USD
CY2019Q4	us-gaap	Residual Value Of Leased Asset ResidualValueOfLeasedAsset	4000000.0	USD
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	4506000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1010000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	4811000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1146000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	77446000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	1105000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	80621000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	81726000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	2950000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	2101000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	841000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	2942000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P19Y2M12D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P1Y
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	6812000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	6916000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	6986000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	7150000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	7185000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	123784000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	158833000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	77107000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	81726000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	1105000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	80621000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	700000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	4597000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	835000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	78590000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	1386000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	4629000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	120000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7577000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	312000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	1800000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	500000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	933000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	575000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	659000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	2592000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	1597000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	1830000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	841000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	430000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	531000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	304500000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	149100000	USD
CY2020Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.005	number
CY2019Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.020	number
CY2020	nwn	Commercial Paper Maximum Maturity CommercialPaperMaximumMaturity	P166D
CY2020	nwn	Commercial Paper Average Maturity CommercialPaperAverageMaturity	P47D
CY2019Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	1000000.0	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	955400000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	881100000	USD
CY2020Q4	us-gaap	Ratio Of Indebtedness To Net Capital1 RatioOfIndebtednessToNetCapital1	0.586	number
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	962905000	USD
CY2019Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	886776000	USD
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	7480000	USD
CY2019Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	5712000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	955425000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	881064000	USD
CY2020Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	1136311000	USD
CY2019Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	957268000	USD
CY2020	us-gaap	Defined Benefit Plan Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate	2026
CY2020Q4	nwn	Defined Benefit Plan Health Care Cost Trend Rate Assumed Thereafter DefinedBenefitPlanHealthCareCostTrendRateAssumedThereafter	0.0350	number
CY2020Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0475	number
CY2020	nwn	Differences Regulatory Commission DifferencesRegulatoryCommission	-3960000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	4422000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	4927000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	19185000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	16370000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	19222000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6389000	USD
CY2019	nwn	Differences Regulatory Commission DifferencesRegulatoryCommission	-5772000	USD
CY2018	nwn	Differences Regulatory Commission DifferencesRegulatoryCommission	1302000	USD
CY2020	nwn	Deferred Tax Rate Differential Post Tcja DeferredTaxRateDifferentialPostTCJA	0	USD
CY2020	nwn	Regulatory Settlement RegulatorySettlement	0	USD
CY2019	nwn	Deferred Tax Rate Differential Post Tcja DeferredTaxRateDifferentialPostTCJA	0	USD
CY2018	nwn	Deferred Tax Rate Differential Post Tcja DeferredTaxRateDifferentialPostTCJA	-76000	USD
CY2019	nwn	Regulatory Settlement RegulatorySettlement	-1129000	USD
CY2018	nwn	Regulatory Settlement RegulatorySettlement	0	USD
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-532000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1249000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1184000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	21082000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12642000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	24191000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.231	number
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.162	number
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.264	number
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	10106000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	5530000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	8953000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	5971000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16077000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1667000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	3785000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	7197000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	12738000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	2888000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	1515000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	9001000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2117000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3930000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2452000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	5005000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	5445000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	11453000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	21082000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12642000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	269886000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Goodwill And Intangible Assets DeferredTaxAssetsGoodwillAndIntangibleAssets	2723000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Other DeferredTaxAssetsTaxCreditCarryforwardsOther	861000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Other DeferredTaxAssetsTaxCreditCarryforwardsOther	162000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1407000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	0	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	39396000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	40133000	USD
CY2020Q4	nwn	Deferred Tax Liabilities Lease Right Of Use Assets DeferredTaxLiabilitiesLeaseRightOfUseAssets	21613000	USD
CY2019Q4	nwn	Deferred Tax Liabilities Lease Right Of Use Assets DeferredTaxLiabilitiesLeaseRightOfUseAssets	778000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	748000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	400257000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	353562000	USD
CY2020Q4	nwn	Deferred Tax Assets Lease Liabilities DeferredTaxAssetsLeaseLiabilities	21622000	USD
CY2019Q4	nwn	Deferred Tax Assets Lease Liabilities DeferredTaxAssetsLeaseLiabilities	775000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Goodwill And Intangible Assets DeferredTaxAssetsGoodwillAndIntangibleAssets	4485000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	80965000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	57919000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	319292000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	295643000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Alternative Minimum Tax DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax	100000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21	number
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35	number
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2654770000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2438899000	USD
CY2020	nwn	Percentage Of Equity Method Investment Sold PercentageOfEquityMethodInvestmentSold	100	number
CY2020	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	500000	USD
CY2020Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	49241000	USD
CY2019Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	49837000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	0	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	13472000	USD
CY2020Q4	us-gaap	Other Investments OtherInvestments	18000	USD
CY2019Q4	us-gaap	Other Investments OtherInvestments	24000	USD
CY2020Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	49259000	USD
CY2019Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	63333000	USD
CY2020	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	500000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	69200000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	49900000	USD
CY2020	us-gaap	Derivative Gain On Derivative DerivativeGainOnDerivative	2300000	USD
CY2019	us-gaap	Derivative Gain On Derivative DerivativeGainOnDerivative	17900000	USD
CY2020	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	13100000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	-12800000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	7500000	USD
CY2020Q4	nwn	Site Contingency Numberof Remediation Projects SiteContingencyNumberofRemediationProjects	2	number
CY2019Q4	nwn	Prudent Costs Deferred During Period PrudentCostsDeferredDuringPeriod	3000000.0	USD
	nwn	Prudent Costs Deferred During Period PrudentCostsDeferredDuringPeriod	1500000	USD
CY2020	nwn	Insurance Proceeds Amortization Period InsuranceProceedsAmortizationPeriod	P10Y6M
CY2020	nwn	Cost Recovery Period CostRecoveryPeriod	P3Y
CY2020	nwn	Total Dividends Paid To Registrant Consolidated Subsidiaries TotalDividendsPaidToRegistrantConsolidatedSubsidiaries	74400000	USD
CY2019	nwn	Total Dividends Paid To Registrant Consolidated Subsidiaries TotalDividendsPaidToRegistrantConsolidatedSubsidiaries	88400000	USD
CY2018Q4	nwn	Total Dividends Paid To Registrant Consolidated Subsidiaries TotalDividendsPaidToRegistrantConsolidatedSubsidiaries	0	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	673000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	890000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	2333000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	677000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	3219000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	977000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	450000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	0	USD
CY2019	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	754000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	673000	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	956000	USD
CY2018	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	680000	USD
CY2018	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	0	USD
CY2018	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	659000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	977000	USD

Files In Submission

Name	View Source	Status
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0001733998-21-000006-index.html	Edgar Link	pending
0001733998-21-000006.txt	Edgar Link	pending
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ex311q42020_ceo.htm	Edgar Link	pending
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exhibit3brestatedarticleso.htm	Edgar Link	pending
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$NWN
Northwest Natural Holding Co Stock $nwn

2019 Q4 Form 10-K Financial Statement

#000173399821000006 Filed on February 26, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NWN Northwest Natural Holding Co Stock $nwn

2019 Q4 Form 10-K Financial Statement

#000173399821000006 Filed on February 26, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NWN
Northwest Natural Holding Co Stock $nwn