$SWX
Southwest Gas Holdings, Inc. Stock $swx

$swx Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000169211520000016 Filed on March 02, 2020

Income Statement

Concept	2019 Q4	2018 Q4	2018 Q3
Revenue	$848.1M	$786.7M	$668.1M
YoY Change	7.82%	6.24%	12.64%
Cost Of Revenue	$92.30M	$100.3M	$395.9M
YoY Change	-7.98%	7.62%	15.54%
Gross Profit	$755.8M	$686.4M	$272.3M
YoY Change	10.11%	6.06%	8.69%
Gross Profit Margin	89.11%	87.26%	40.75%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$79.90M	$63.30M	$62.10M
YoY Change	26.22%	2.26%	6.15%
% of Gross Profit	10.57%	9.22%	22.81%
Operating Expenses	$617.6M	$551.5M	$578.6M
YoY Change	11.99%	7.78%	12.85%
Operating Profit	$138.2M	$134.9M	$39.68M
YoY Change	2.48%	-0.49%	13.41%
Interest Expense	-$23.70M	-$34.20M	$24.55M
YoY Change	-30.7%	91.06%	25.93%
% of Operating Profit	-17.15%	-25.36%	61.86%
Other Income/Expense, Net	-$1.600M	-$2.900M	-$23.66M
YoY Change	-44.83%	-17.14%	10.18%
Pretax Income	$112.9M	$97.70M	$16.02M
YoY Change	15.56%	-14.37%	18.56%
Income Tax	$21.00M	$28.30M	$3.691M
% Of Pretax Income	18.6%	28.97%	23.04%
Net Earnings	$91.72M	$69.30M	$12.33M
YoY Change	32.34%	-28.16%	20.84%
Net Earnings / Revenue	10.81%	8.81%	1.85%
Basic Earnings Per Share	$1.67	$1.36	$0.25
Diluted Earnings Per Share	$1.67	$1.36	$0.25
COMMON SHARES
Basic Shares Outstanding	54.63M shares	49.43M shares	49.49M shares
Diluted Shares Outstanding			49.55M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$49.50M	$87.10M	$70.20M
YoY Change	-43.17%	81.08%	18.58%
Cash & Equivalents	$49.54M	$85.36M	$69.17M
Short-Term Investments	$0.00	$1.800M	$1.000M
Other Short-Term Assets	$225.4M	$246.8M	$219.2M
YoY Change	-8.67%	40.71%	58.5%
Inventory
Prepaid Expenses
Receivables	$474.1M	$413.9M	$347.6M
Other Receivables	$31.70M	$14.70M	$49.60M
Total Short-Term Assets	$859.9M	$839.8M	$721.2M
YoY Change	2.39%	27.81%	33.82%
LONG-TERM ASSETS
Property, Plant & Equipment	$6.337B	$5.602B	$5.213B
YoY Change	13.12%	17.85%	12.32%
Goodwill	$343.0M	$359.0M	$176.1M
YoY Change	-4.46%	100.23%	19.07%
Intangibles
YoY Change
Long-Term Investments		$100.0K	$100.0K
YoY Change		-92.31%
Other Assets	$496.9M	$440.9M	$419.8M
YoY Change	12.72%	-1.46%	1.99%
Total Long-Term Assets	$7.310B	$6.518B	$5.933B
YoY Change	12.15%	16.81%	11.61%
TOTAL ASSETS
Total Short-Term Assets	$859.9M	$839.8M	$721.2M
Total Long-Term Assets	$7.310B	$6.518B	$5.933B
Total Assets	$8.170B	$7.358B	$6.655B
YoY Change	11.04%	17.97%	13.66%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$238.9M	$249.0M	$172.2M
YoY Change	-4.05%	9.06%	8.07%
Accrued Expenses	$79.10M	$64.90M	$82.30M
YoY Change	21.88%	5.19%	11.97%
Deferred Revenue	$69.17M
YoY Change
Short-Term Debt	$211.0M	$152.0M	$31.50M
YoY Change	38.82%	-29.14%	-71.49%
Long-Term Debt Due	$163.5M	$33.06M	$33.43M
YoY Change	394.59%	30.43%	17.49%
Total Short-Term Liabilities	$1.080B	$938.6M	$712.7M
YoY Change	15.04%	15.05%	8.58%
LONG-TERM LIABILITIES
Long-Term Debt	$2.300B	$2.107B	$2.124B
YoY Change	9.17%	17.16%	22.61%
Other Long-Term Liabilities	$2.199B	$1.978B	$1.872B
YoY Change	11.16%	9.29%	6.8%
Total Long-Term Liabilities	$4.500B	$4.086B	$3.996B
YoY Change	10.13%	13.21%	14.66%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.080B	$938.6M	$712.7M
Total Long-Term Liabilities	$4.500B	$4.086B	$3.996B
Total Liabilities	$5.580B	$5.024B	$4.709B
YoY Change	11.05%	13.55%	13.69%
SHAREHOLDERS EQUITY
Retained Earnings	$1.039B	$944.3M	$902.7M
YoY Change	10.04%	10.13%	15.01%
Common Stock	$1.524B	$1.360B	$1.097B
YoY Change	11.99%	35.36%	12.67%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.506B	$2.252B	$1.946B
YoY Change
Total Liabilities & Shareholders Equity	$8.170B	$7.358B	$6.655B
YoY Change	11.04%	17.97%	13.66%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018 Q3
OPERATING ACTIVITIES
Net Income	$91.72M	$69.30M	$12.33M
YoY Change	32.34%	-28.16%	20.84%
Depreciation, Depletion And Amortization	$79.90M	$63.30M	$62.10M
YoY Change	26.22%	2.26%	6.15%
Cash From Operating Activities	$121.9M	$121.5M	$160.4M
YoY Change	0.33%	71.61%	58.81%
INVESTING ACTIVITIES
Capital Expenditures	-$218.7M	-$205.7M	-$221.2M
YoY Change	6.32%	18.49%	17.78%
Acquisitions
YoY Change
Other Investing Activities	-$21.90M	-$244.3M	$4.200M
YoY Change	-91.04%	189.45%	147.06%
Cash From Investing Activities	-$240.6M	-$450.0M	-$217.0M
YoY Change	-46.53%	74.35%	16.67%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	139.7M	345.1M	90.80M
YoY Change	-59.52%	100.76%	-20.49%
NET CHANGE
Cash From Operating Activities	121.9M	121.5M	160.4M
Cash From Investing Activities	-240.6M	-450.0M	-217.0M
Cash From Financing Activities	139.7M	345.1M	90.80M
Net Change In Cash	21.00M	16.60M	34.20M
YoY Change	26.51%	-207.79%	17.12%
FREE CASH FLOW
Cash From Operating Activities	$121.9M	$121.5M	$160.4M
Capital Expenditures	-$218.7M	-$205.7M	-$221.2M
Free Cash Flow	$340.6M	$327.2M	$381.6M
YoY Change	4.1%	33.88%	32.13%

Facts In Submission

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CY2019	dei	Entity File Number EntityFileNumber	001-37976
CY2019	dei	Entity Registrant Name EntityRegistrantName	Southwest Gas Holdings, Inc.
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	81-3881866
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	5241 Spring Mountain Road
CY2019	dei	Entity Address Address Line2 EntityAddressAddressLine2	Post Office Box 98510
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Las Vegas,
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	NV
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CY2019	dei	City Area Code CityAreaCode	(702)
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CY2019	dei	Security12b Title Security12bTitle	Southwest Gas Holdings, Inc. Common Stock, $1 par value
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CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-84094000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	272670000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	243336000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	259030000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56023000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	61684000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	65088000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	216647000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	181652000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	193942000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	2711000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-625000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	101000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	213936000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	182277000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	193841000	USD
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.94
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.69
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.04
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.94
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.68
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.04
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54245000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49419000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	47965000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	54312000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49476000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	47991000	shares
CY2019	us-gaap	Profit Loss ProfitLoss	216647000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	181652000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	193942000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-54026000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-15524000	USD
CY2017	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-32701000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	966000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	1015000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	828000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-17766000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-25549000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-15776000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Costs Credit Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax	1426000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Costs Credit Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Costs Credit Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax	0	USD
CY2019	swx	Other Comprehensive Income Defined Benefit Plans Regulatory Adjustment Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansRegulatoryAdjustmentNetOfTax	-28077000	USD
CY2018	swx	Other Comprehensive Income Defined Benefit Plans Regulatory Adjustment Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansRegulatoryAdjustmentNetOfTax	6257000	USD
CY2017	swx	Other Comprehensive Income Defined Benefit Plans Regulatory Adjustment Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansRegulatoryAdjustmentNetOfTax	-12590000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	8643000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-4783000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	3507000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-2541000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-2541000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-2073000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2541000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2541000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2073000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	2038000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-3010000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	1771000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-4064000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4314000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	337000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	212583000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	185966000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	194279000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	2711000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-625000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	112000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	209872000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	186591000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	194167000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	216647000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	181652000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	193942000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	303237000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	249212000	USD
CY2017	us-gaap	Depreciation And Amortization DepreciationAndAmortization	250951000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-54162000	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-51041000	USD
CY2017	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-63389000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	54245000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	15862000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	40947000	USD
CY2019	us-gaap	Increase Decrease In Unbilled Receivables IncreaseDecreaseInUnbilledReceivables	1900000	USD
CY2018	us-gaap	Increase Decrease In Unbilled Receivables IncreaseDecreaseInUnbilledReceivables	-1000000	USD
CY2017	us-gaap	Increase Decrease In Unbilled Receivables IncreaseDecreaseInUnbilledReceivables	2000000	USD
CY2019	us-gaap	Increase Decrease In Deferred Gas Cost IncreaseDecreaseInDeferredGasCost	58491000	USD
CY2018	us-gaap	Increase Decrease In Deferred Gas Cost IncreaseDecreaseInDeferredGasCost	-82574000	USD
CY2017	us-gaap	Increase Decrease In Deferred Gas Cost IncreaseDecreaseInDeferredGasCost	95608000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-1865000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	11778000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	19961000	USD
CY2019	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	5243000	USD
CY2018	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	-11955000	USD
CY2017	us-gaap	Increase Decrease In Accrued Taxes Payable IncreaseDecreaseInAccruedTaxesPayable	2112000	USD
CY2019	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	-74137000	USD
CY2018	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	54073000	USD
CY2017	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	8203000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	5473000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	1703000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	4196000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	6896000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	6111000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	10888000	USD
CY2019	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	4161000	USD
CY2018	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	3627000	USD
CY2017	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2296000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	21051000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	5738000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	22269000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-12764000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	38446000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	4231000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	500372000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	528856000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	369955000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	938148000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	765914000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	623649000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	47638000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	251373000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	94204000	USD
CY2019	us-gaap	Increase Decrease In Customer Advances IncreaseDecreaseInCustomerAdvances	19001000	USD
CY2018	us-gaap	Increase Decrease In Customer Advances IncreaseDecreaseInCustomerAdvances	13463000	USD
CY2017	us-gaap	Increase Decrease In Customer Advances IncreaseDecreaseInCustomerAdvances	323000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-15153000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-4341000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-16645000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-951632000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-999483000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-700885000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	157946000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	354402000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	41155000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	116127000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	100240000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	92130000	USD
CY2019	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	0	USD
CY2018	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	0	USD
CY2017	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	204000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	531596000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	565172000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	407063000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	213789000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	237758000	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	338969000	USD
CY2019	swx	Proceeds From Repayments Of Lines Of Credit And Commercial Paper ProceedsFromRepaymentsOfLinesOfCreditAndCommercialPaper	0	USD
CY2018	swx	Proceeds From Repayments Of Lines Of Credit And Commercial Paper ProceedsFromRepaymentsOfLinesOfCreditAndCommercialPaper	0	USD
CY2017	swx	Proceeds From Repayments Of Lines Of Credit And Commercial Paper ProceedsFromRepaymentsOfLinesOfCreditAndCommercialPaper	145000000	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	59000000	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-62500000	USD
CY2017	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	214500000	USD
CY2019	us-gaap	Repayments Of Debt And Capital Lease Obligations RepaymentsOfDebtAndCapitalLeaseObligations	212000	USD
CY2018	us-gaap	Repayments Of Debt And Capital Lease Obligations RepaymentsOfDebtAndCapitalLeaseObligations	648000	USD
CY2017	us-gaap	Repayments Of Debt And Capital Lease Obligations RepaymentsOfDebtAndCapitalLeaseObligations	980000	USD
CY2019	us-gaap	Payments For Repurchase Of Redeemable Noncontrolling Interest PaymentsForRepurchaseOfRedeemableNoncontrollingInterest	0	USD
CY2018	us-gaap	Payments For Repurchase Of Redeemable Noncontrolling Interest PaymentsForRepurchaseOfRedeemableNoncontrollingInterest	0	USD
CY2017	us-gaap	Payments For Repurchase Of Redeemable Noncontrolling Interest PaymentsForRepurchaseOfRedeemableNoncontrollingInterest	23000000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	1858000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3110000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3176000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1276000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2744000	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-3074000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	415280000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	512574000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	346185000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	158000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-208000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	301000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-35822000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	41739000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	15556000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	85361000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	43622000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	28066000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	49539000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	85361000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	43622000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	102258000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	86562000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	71943000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	2752000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1221000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	5673000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2505914000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2251590000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1812403000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2180
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2080.00
CY2017	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1980
CY2019Q4	us-gaap	Property Plant And Equipment Other Net PropertyPlantAndEquipmentOtherNet	18814000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Other Net PropertyPlantAndEquipmentOtherNet	14153000	USD
CY2019Q4	swx	Other Property And Investments OtherPropertyAndInvestments	784173000	USD
CY2018Q4	swx	Other Property And Investments OtherPropertyAndInvestments	623551000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	10700000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	7600000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4100000	USD
CY2019Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	32000000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2017Q4	us-gaap	Goodwill Goodwill	179314000	USD
CY2018	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-8945000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	359045000	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	5150000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	343023000	USD
CY2019	swx	Public Utilities Allowancefor Funds Used During Construction Capitalized Debt Portion PublicUtilitiesAllowanceforFundsUsedDuringConstructionCapitalizedDebtPortion	4558000	USD
CY2018	swx	Public Utilities Allowancefor Funds Used During Construction Capitalized Debt Portion PublicUtilitiesAllowanceforFundsUsedDuringConstructionCapitalizedDebtPortion	3264000	USD
CY2017	swx	Public Utilities Allowancefor Funds Used During Construction Capitalized Debt Portion PublicUtilitiesAllowanceforFundsUsedDuringConstructionCapitalizedDebtPortion	1666000	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	4161000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	3627000	USD
CY2017	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	2296000	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	8719000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	6891000	USD
CY2017	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	3962000	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.0536
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.0585
CY2017	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.0595
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	10085000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-17426000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-6030000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54245000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49419000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	47965000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	12000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	25000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	8000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	55000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	32000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	18000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	54312000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49476000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	47991000	shares
CY2019	swx	Number Of Performance Share Units Granted NumberOfPerformanceShareUnitsGranted	46000	shares
CY2018	swx	Number Of Performance Share Units Granted NumberOfPerformanceShareUnitsGranted	23000	shares
CY2017	swx	Number Of Performance Share Units Granted NumberOfPerformanceShareUnitsGranted	7000	shares
CY2019Q4	swx	Public Utilities Property Plantand Equipment Gas Plant PublicUtilitiesPropertyPlantandEquipmentGasPlant	7813221000	USD
CY2018Q4	swx	Public Utilities Property Plantand Equipment Gas Plant PublicUtilitiesPropertyPlantandEquipmentGasPlant	7134239000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	2313050000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	2234029000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	185026000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	193028000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	5685197000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	5093238000	USD
CY2019	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.027
CY2018	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.027
CY2017	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.030
CY2019	us-gaap	Lease Cost LeaseCost	30154000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	12444000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	33000	USD
CY2019	swx	Finance Lease Principal Payments Leases Entered Or Modified During Period FinanceLeasePrincipalPaymentsLeasesEnteredOrModifiedDuringPeriod	212000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	24687000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	13839000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	14264000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	13769000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	355000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	14124000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y3M
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P2Y1M17D
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0403
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0610
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-4064000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	64047000	USD
CY2017	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	67236000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	10951000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	8019000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	6059000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	5326000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	3760000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	10688000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	44803000	USD
CY2019	swx	Number Of Customers NumberOfCustomers	2000000	Customer
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1385294000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1305974000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1262881000	USD
CY2019	swx	Alternative Revenue Program Revenues Deferrals AlternativeRevenueProgramRevenuesDeferrals	-25112000	USD
CY2018	swx	Alternative Revenue Program Revenues Deferrals AlternativeRevenueProgramRevenuesDeferrals	45979000	USD
CY2017	swx	Alternative Revenue Program Revenues Deferrals AlternativeRevenueProgramRevenuesDeferrals	35347000	USD
CY2019	swx	Other Revenue OtherRevenue	8757000	USD
CY2018	swx	Other Revenue OtherRevenue	5775000	USD
CY2017	swx	Other Revenue OtherRevenue	4080000	USD
CY2019	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	1368939000	USD
CY2018	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	1357728000	USD
CY2017	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	1302308000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	223904000	USD
CY2018Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	186249000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	99399000	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	87520000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	4525000	USD
CY2018Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	4211000	USD
CY2019Q4	swx	Billed On Completed Contracts And Contracts In Progress BilledOnCompletedContractsAndContractsInProgress	216268000	USD
CY2018Q4	swx	Billed On Completed Contracts And Contracts In Progress BilledOnCompletedContractsAndContractsInProgress	184100000	USD
CY2019Q4	us-gaap	Other Receivables OtherReceivables	8456000	USD
CY2018Q4	us-gaap	Other Receivables OtherReceivables	2588000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	224724000	USD
CY2018Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	186688000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	820000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	439000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	223904000	USD
CY2018Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	186249000	USD
CY2019	swx	Gas Utility Customer Accounts Receivable GasUtilityCustomerAccountsReceivable	148173000	USD
CY2018	swx	Gas Utility Customer Accounts Receivable GasUtilityCustomerAccountsReceivable	138149000	USD
CY2019Q4	us-gaap	Regulatory Assets RegulatoryAssets	582759000	USD
CY2018Q4	us-gaap	Regulatory Assets RegulatoryAssets	573591000	USD
CY2019Q4	swx	Net Regulatory Liabilities NetRegulatoryLiabilities	363890000	USD
CY2018Q4	swx	Net Regulatory Liabilities NetRegulatoryLiabilities	376777000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-5992000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-1928000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	6628000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	2314000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4314000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	1208000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	871000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	337000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.24
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.38
CY2019Q4	us-gaap	Interest Rate Cash Flow Hedge Gain Loss To Be Reclassified During Next12 Months Net InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet	2500000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-51988000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.24
CY2019Q4	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains Losses Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax	483074000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains Losses Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax	435364000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax	-3641000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax	-3033000	USD
CY2019Q4	swx	Defined Benefit Plan Accumulated Other Comprehensive Income Loss Amount Recognized Regulatory Assets Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAmountRecognizedRegulatoryAssetsBeforeTax	-420114000	USD
CY2018Q4	swx	Defined Benefit Plan Accumulated Other Comprehensive Income Loss Amount Recognized Regulatory Assets Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAmountRecognizedRegulatoryAssetsBeforeTax	-383170000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax	-66601000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax	-55227000	USD
CY2019Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	4200000	shares
CY2019Q3	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	60000000	shares
CY2019Q3	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	120000000	shares
CY2019Q4	swx	Debt Instrument Percentage Of Total With Interest Rates Reference To Libor And Due After2021 DebtInstrumentPercentageOfTotalWithInterestRatesReferenceToLIBORAndDueAfter2021	0.19
CY2019	swx	Debt Instrument Covenant Compliance Credit Risk Exposure Amount DebtInstrumentCovenantComplianceCreditRiskExposureAmount	2400000000	USD
CY2019	swx	Equity Cushion Relating To Minimum Net Worth Requirement EquityCushionRelatingToMinimumNetWorthRequirement	1500000000	USD
CY2019	swx	Percentage Of Maximum Dividend Payout Restriction PercentageOfMaximumDividendPayoutRestriction	0.60
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	163512000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	33785000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	460783000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	240681000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	USD
CY2019Q4	swx	Sharebased Compensation Arrangement By Sharebased Payment Award Number Of Plans SharebasedCompensationArrangementBySharebasedPaymentAwardNumberOfPlans	3	plan
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	5154000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	4644000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	6751000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1627000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1467000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4137000	USD
CY2019Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	3600000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y8M12D
CY2019	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent Of Match DefinedContributionPlanEmployerMatchingContributionPercentOfMatch	0.035
CY2019	swx	Employees Investment Plan Cost EmployeesInvestmentPlanCost	5700000	USD
CY2018	swx	Employees Investment Plan Cost EmployeesInvestmentPlanCost	5500000	USD
CY2017	swx	Employees Investment Plan Cost EmployeesInvestmentPlanCost	5100000	USD
CY2019	swx	Deferment Of Annual Cash Compensation DefermentOfAnnualCashCompensation	1
CY2019	swx	Matching Contribution Of Employer MatchingContributionOfEmployer	0.035
CY2019	swx	Floating Interest Rate Index FloatingInterestRateIndex	1.50
CY2019	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Discount Rate DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate	0.0350
CY2018	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Discount Rate DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate	0.0450
CY2019	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Rate Of Compensation Increase DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease	0.0325
CY2018	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Rate Of Compensation Increase DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease	0.0325
CY2019	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets	0.0675
CY2018	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets	0.0700
CY2019	swx	Future Estimated Funding Amount FutureEstimatedFundingAmount	105000000	USD
CY2017	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	392763000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-6030000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-71087000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-20426000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-43027000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	1271000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	1335000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	1335000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-23376000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-33617000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-25445000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Benefit Plan Improvement Tax Effect OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect	-1878000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Benefit Plan Improvement Tax Effect OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect	0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Benefit Plan Improvement Tax Effect OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect	0	USD
CY2019	swx	Defined Benefit Plan Regulatory Adjustment Before Tax Net DefinedBenefitPlanRegulatoryAdjustmentBeforeTaxNet	-36944000	USD
CY2018	swx	Defined Benefit Plan Regulatory Adjustment Before Tax Net DefinedBenefitPlanRegulatoryAdjustmentBeforeTaxNet	8233000	USD
CY2017	swx	Defined Benefit Plan Regulatory Adjustment Before Tax Net DefinedBenefitPlanRegulatoryAdjustmentBeforeTaxNet	-12340000	USD
CY2019	us-gaap	Defined Benefit Plan Amounts Recognized In Other Comprehensive Income Loss Net Gain Loss Before Tax DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax	-11374000	USD
CY2018	us-gaap	Defined Benefit Plan Amounts Recognized In Other Comprehensive Income Loss Net Gain Loss Before Tax DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax	6293000	USD
CY2017	us-gaap	Defined Benefit Plan Amounts Recognized In Other Comprehensive Income Loss Net Gain Loss Before Tax DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax	-3907000	USD
CY2019	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	42465000	USD
CY2018	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	51332000	USD
CY2017	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	44593000	USD
CY2019	us-gaap	Amount Recognized In Net Periodic Benefit Cost And Other Comprehensive Income Loss Before Tax AmountRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveIncomeLossBeforeTax	53839000	USD
CY2018	us-gaap	Amount Recognized In Net Periodic Benefit Cost And Other Comprehensive Income Loss Before Tax AmountRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveIncomeLossBeforeTax	45039000	USD
CY2017	us-gaap	Amount Recognized In Net Periodic Benefit Cost And Other Comprehensive Income Loss Before Tax AmountRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveIncomeLossBeforeTax	48500000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	1027831000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	837955000	USD
CY2019	swx	Deferred Compensation Arrangement With Individual Maximum Percentage Of Deferral DeferredCompensationArrangementWithIndividualMaximumPercentageOfDeferral	0.80
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-869000	USD
CY2019	swx	Deferred Compensation Arrangement With Individual Matching Percentage DeferredCompensationArrangementWithIndividualMatchingPercentage	1
CY2019	swx	Deferred Compensation Arrangement With Individual Maximum Percentage Of Salary With Matching DeferredCompensationArrangementWithIndividualMaximumPercentageOfSalaryWithMatching	0.05
CY2019	swx	Deferred Compensation Arrangement With Individual Vesting Percentage Of Deferral DeferredCompensationArrangementWithIndividualVestingPercentageOfDeferral	1
CY2019	swx	Multiemployer Plan Special Surcharges MultiemployerPlanSpecialSurcharges	0	USD
CY2019Q4	swx	Multiemployer Plan Number Of Critical Plan MultiemployerPlanNumberOfCriticalPlan	2	plan
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	261525000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	235120000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	246131000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	11145000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	8216000	USD
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Files In Submission

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$SWX
Southwest Gas Holdings, Inc. Stock $swx

2019 Q4 Form 10-K Financial Statement

#000169211520000016 Filed on March 02, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SWX Southwest Gas Holdings, Inc. Stock $swx

2019 Q4 Form 10-K Financial Statement

#000169211520000016 Filed on March 02, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SWX
Southwest Gas Holdings, Inc. Stock $swx