$ATO
ATMOS ENERGY CORP Stock $ato

$ato Overview Financials Valuation SEC Filings Company Website

2024 Q4 Form 10-K Financial Statement

#000073180224000030 Filed on November 18, 2024

Income Statement

Concept	2024 Q4	2024 Q3	2024
Revenue		$657.9M	$4.165B
YoY Change		11.97%	-2.58%
Cost Of Revenue		-$26.88M	$933.7M
YoY Change		-939.94%	-35.7%
Gross Profit		$684.8M	$3.231B
YoY Change		17.18%	14.46%
Gross Profit Margin		104.09%	77.58%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization		$173.5M	$670.0M
YoY Change		8.95%	10.86%
% of Gross Profit		25.33%	20.73%
Operating Expenses		$499.8M	$1.876B
YoY Change		16.13%	6.84%
Operating Profit		$185.0M	$1.355B
YoY Change		20.13%	27.01%
Interest Expense		-$42.16M	$22.89M
YoY Change		32.56%	-83.33%
% of Operating Profit		-22.79%	1.69%
Other Income/Expense, Net		$16.58M	$71.05M
YoY Change		10.5%	1.82%
Pretax Income		$159.4M	$1.236B
YoY Change		16.11%	23.62%
Income Tax		$25.40M	$192.9M
% Of Pretax Income		15.94%	15.61%
Net Earnings		$134.0M	$1.043B
YoY Change		13.04%	17.73%
Net Earnings / Revenue		20.36%	25.04%
Basic Earnings Per Share			$6.83
Diluted Earnings Per Share		$0.86	$6.83
COMMON SHARES
Basic Shares Outstanding	155.4M shares	155.2M shares	152.5M shares
Diluted Shares Outstanding			152.7M shares

Balance Sheet

Concept	2024 Q3	2024
SHORT-TERM ASSETS
Cash & Short-Term Investments	$417.9M	$307.3M
YoY Change	248.26%	1948.93%
Cash & Equivalents	$307.3M	$307.3M
Short-Term Investments	$110.6M
Other Short-Term Assets	$288.1M	$258.3M
YoY Change	-1.36%	4.15%
Inventory	$169.5M	$186.5M
Prepaid Expenses	$74.78M
Receivables	$365.9M	$307.4M
Other Receivables	$0.00	$72.85M
Total Short-Term Assets	$1.132B	$1.132B
YoY Change	27.83%	27.8%
LONG-TERM ASSETS
Property, Plant & Equipment	$22.20B	$22.20B
YoY Change	13.25%	11.97%
Goodwill	$731.3M
YoY Change	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$1.044B	$1.044B
YoY Change	-13.11%	19.55%
Total Long-Term Assets	$24.06B	$24.06B
YoY Change	11.24%	11.24%
TOTAL ASSETS
Total Short-Term Assets	$1.132B	$1.132B
Total Long-Term Assets	$24.06B	$24.06B
Total Assets	$25.19B	$25.19B
YoY Change	11.89%	11.89%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$445.4M	$341.9M
YoY Change	32.56%	56.86%
Accrued Expenses		$308.0M
YoY Change		8.85%
Deferred Revenue	$62.09M
YoY Change	-4.87%
Short-Term Debt	$0.00	$0.00
YoY Change	-100.0%	-100.0%
Long-Term Debt Due	$9.858M	$9.858M
YoY Change	-10.38%	-10.38%
Total Short-Term Liabilities	$1.206B	$1.206B
YoY Change	-10.85%	-10.87%
LONG-TERM LIABILITIES
Long-Term Debt	$7.861B	$7.861B
YoY Change	18.4%	18.4%
Other Long-Term Liabilities	$691.9M	$1.377B
YoY Change	15.34%	2.0%
Total Long-Term Liabilities	$691.9M	$9.238B
YoY Change	15.34%	15.63%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.206B	$1.206B
Total Long-Term Liabilities	$691.9M	$9.238B
Total Liabilities	$1.898B	$13.04B
YoY Change	-2.8%	11.93%
SHAREHOLDERS EQUITY
Retained Earnings	$4.217B
YoY Change	15.0%
Common Stock	$7.475B
YoY Change	11.82%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$12.16B	$12.16B
YoY Change
Total Liabilities & Shareholders Equity	$25.19B	$25.19B
YoY Change	11.89%	11.89%

Cashflow Statement

Concept	2024 Q3	2024
OPERATING ACTIVITIES
Net Income	$134.0M	$1.043B
YoY Change	13.04%	17.73%
Depreciation, Depletion And Amortization	$173.5M	$670.0M
YoY Change	8.95%	10.86%
Cash From Operating Activities	$330.7M	$1.734B
YoY Change	38.83%	-49.89%
INVESTING ACTIVITIES
Capital Expenditures	$808.0M	$2.937B
YoY Change	11.83%	4.67%
Acquisitions
YoY Change
Other Investing Activities	$4.312M	-$16.06M
YoY Change	-4.18%	-15.5%
Cash From Investing Activities	-$803.7M	-$2.923B
YoY Change	11.93%	4.56%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$750.0M
YoY Change		-7.06%
Debt Paid & Issued, Net		$0.00
YoY Change		-100.0%
Cash From Financing Activities	102.6M	$1.479B
YoY Change	-76.73%	-312.21%
NET CHANGE
Cash From Operating Activities	330.7M	$1.734B
Cash From Investing Activities	-803.7M	-$2.923B
Cash From Financing Activities	102.6M	$1.479B
Net Change In Cash	-370.4M	$289.6M
YoY Change	849.76%	-996.45%
FREE CASH FLOW
Cash From Operating Activities	$330.7M	$1.734B
Capital Expenditures	$808.0M	$2.937B
Free Cash Flow	-$477.3M	-$1.203B
YoY Change	-1.44%	-284.08%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2024	dei	Document Type DocumentType	10-K
CY2024	dei	Document Period End Date DocumentPeriodEndDate	2024-09-30
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	299309000	usd
CY2024	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2024
CY2024	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2024	dei	Amendment Flag AmendmentFlag	false
CY2024	dei	Document Transition Report DocumentTransitionReport	false
CY2024	dei	Entity File Number EntityFileNumber	1-10042
CY2024	dei	Entity Registrant Name EntityRegistrantName	Atmos Energy Corp
CY2024	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	TX
CY2024	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	75-1743247
CY2024	dei	Entity Address Address Line2 EntityAddressAddressLine2	5430 LBJ Freeway
CY2024	dei	Entity Address City Or Town EntityAddressCityOrTown	Dallas
CY2024	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
CY2024	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	75240
CY2024	dei	City Area Code CityAreaCode	972
CY2024	dei	Local Phone Number LocalPhoneNumber	934-9227
CY2024	dei	Security12b Title Security12bTitle	Common stock
CY2024	dei	Trading Symbol TradingSymbol	ATO
CY2024	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2024	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2024	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2024	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2024	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2024	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2024	dei	Entity Small Business EntitySmallBusiness	false
CY2024	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2024	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2024	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2024	dei	Entity Shell Company EntityShellCompany	false
CY2024Q1	dei	Entity Public Float EntityPublicFloat	17825800856	usd
CY2024Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	155399533	shares
CY2024	dei	Auditor Firm AuditorFirmId	42
CY2024	dei	Auditor Name AuditorName	Ernst & Young LLP
CY2024	dei	Auditor Location AuditorLocation	Dallas, Texas
CY2024Q3	ato	Public Utilities Property Plant And Equipment Plant In Service Excluding Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceExcludingConstructionWorkInProgress	24784285000	usd
CY2023Q3	ato	Public Utilities Property Plant And Equipment Plant In Service Excluding Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceExcludingConstructionWorkInProgress	21958447000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	1063798000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	939927000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	25848083000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	22898374000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3643716000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3291791000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	22204367000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	19606583000	usd
CY2024Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	307340000	usd
CY2023Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	15404000	usd
CY2024Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	308856000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	19248000	usd
CY2024Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	37056000	usd
CY2023Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	40840000	usd
CY2024Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	365882000	usd
CY2023Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	328654000	usd
CY2024Q3	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	169508000	usd
CY2023Q3	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	245830000	usd
CY2024Q3	us-gaap	Other Assets Current OtherAssetsCurrent	288068000	usd
CY2024Q3	us-gaap	Assets Current AssetsCurrent	1132314000	usd
CY2023Q3	us-gaap	Assets Current AssetsCurrent	885768000	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	10756000	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	82844000	usd
CY2024Q3	us-gaap	Goodwill Goodwill	731257000	usd
CY2024Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1043683000	usd
CY2024Q3	us-gaap	Assets Assets	25194465000	usd
CY2023Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.005
CY2024Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	200000000	shares
CY2024Q3	us-gaap	Common Stock Value CommonStockValue	776000	usd
CY2024Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	7474559000	usd
CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	465715000	usd
CY2024Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	4216619000	usd
CY2024Q3	us-gaap	Stockholders Equity StockholdersEquity	12157669000	usd
CY2024Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	7783646000	usd
CY2024Q3	ato	Securitized Long Term Debt Excluding Current Maturities SecuritizedLongTermDebtExcludingCurrentMaturities	76871000	usd
CY2024Q3	us-gaap	Capitalization Longterm Debt And Equity CapitalizationLongtermDebtAndEquity	20018186000	usd
CY2024Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2024Q3	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	445397000	usd
CY2024Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	750620000	usd
CY2024Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	1651000	usd
CY2024Q3	ato	Securitized Long Term Debt Current Maturities SecuritizedLongTermDebtCurrentMaturities	8207000	usd
CY2024Q3	us-gaap	Liabilities Current LiabilitiesCurrent	1205875000	usd
CY2024Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	2593342000	usd
CY2024Q3	ato	Change In Tax Rate Deferred Tax Liability ChangeInTaxRateDeferredTaxLiability	177315000	usd
CY2024Q3	ato	Regulatory Cost Of Removal Liability Noncurrent RegulatoryCostOfRemovalLiabilityNoncurrent	507815000	usd
CY2024Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	691932000	usd
CY2024	us-gaap	Revenues Revenues	4165187000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2024	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	819137000	usd
CY2023	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	764906000	usd
CY2024	us-gaap	Depreciation And Amortization DepreciationAndAmortization	669972000	usd
CY2023	us-gaap	Depreciation And Amortization DepreciationAndAmortization	604327000	usd
CY2024	us-gaap	Taxes Other TaxesOther	387023000	usd
CY2023	us-gaap	Taxes Other TaxesOther	386804000	usd
CY2024	us-gaap	Operating Income Loss OperatingIncomeLoss	1355362000	usd
CY2023	us-gaap	Operating Income Loss OperatingIncomeLoss	1067147000	usd
CY2024	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	71046000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	69775000	usd
CY2024	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1235776000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	999641000	usd
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	192881000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113779000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	1042895000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
CY2024	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.83
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.10
CY2024	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.83
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.10
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	145121000	shares
CY2024	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	152666000	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	145166000	shares
CY2024	us-gaap	Net Income Loss NetIncomeLoss	1042895000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
CY2023	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	37000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	126000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	-15432000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	43148000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-53395000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	149290000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-52813000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	149416000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1035278000	usd
CY2022	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	7908000	usd
CY2022	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2398000	usd
CY2022	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	19803000	usd
CY2022Q3	us-gaap	Stockholders Equity StockholdersEquity	9419091000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
CY2023	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.96
CY2023	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	430345000	usd
CY2023	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	806949000	usd
CY2023	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	7429000	usd
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CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
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CY2023	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	604327000	usd
CY2024	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	172707000	usd
CY2024	us-gaap	Share Based Compensation ShareBasedCompensation	10709000	usd
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	10178000	usd
CY2024	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	-6882000	usd
CY2023	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	3639000	usd
CY2024	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	58234000	usd
CY2023	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	64019000	usd
CY2024	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-1546000	usd
CY2023	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	591000	usd
CY2024	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	40909000	usd
CY2023	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-46859000	usd
CY2024	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-76322000	usd
CY2023	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-112111000	usd
CY2024	ato	Increase Decrease In Regulatory Assets Current IncreaseDecreaseInRegulatoryAssetsCurrent	0	usd
CY2023	ato	Increase Decrease In Regulatory Assets Current IncreaseDecreaseInRegulatoryAssetsCurrent	-2021889000	usd
CY2024	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	-17138000	usd
CY2023	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	36041000	usd
CY2022	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-13287000	usd
CY2022	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	40394000	usd
CY2022	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-152274000	usd
CY2022	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	14958000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	977584000	usd
CY2022	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	2444420000	usd
CY2022	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	28285000	usd
CY2022	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	4872000	usd
CY2022Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	51554000	usd
CY2021Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	116723000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2429958000	usd
CY2022	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	184967000	usd
CY2022	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	798802000	usd
CY2022	ato	Proceeds From Issuance Of Securitized Long Term Debt ProceedsFromIssuanceOfSecuritizedLongTermDebt	0	usd
CY2022	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	776805000	usd
CY2022	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	15403000	usd
CY2022	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	-197073000	usd
CY2022	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	usd
CY2022	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	200000000	usd
CY2024	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	492950000	usd
CY2024	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	11844000	usd
CY2023	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	7864000	usd
CY2024	ato	Payments Of Securitized Debt Issuance Costs PaymentsOfSecuritizedDebtIssuanceCosts	0	usd
CY2023	ato	Payments Of Securitized Debt Issuance Costs PaymentsOfSecuritizedDebtIssuanceCosts	1273000	usd
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CY2023	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	usd
CY2024	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1478631000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-696769000	usd
CY2024	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	289608000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-32306000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	19248000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	773890000	usd
CY2024Q3	us-gaap	Assets Assets	25194465000	usd
CY2024Q3	ato	Debt And Equity Securities DebtAndEquitySecurities	110594000	usd
CY2024Q3	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	206882000	usd
CY2024Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	7637000	usd
CY2024	dei	Entity Central Index Key EntityCentralIndexKey	0000731802
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CY2023Q3	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2024#PublicUtilitiesPropertyPlantAndEquipmentNet
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CY2023Q3	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2024#LongTermDebtAndCapitalLeaseObligations
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CY2024	dei	Document Annual Report DocumentAnnualReport	true
CY2024	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--09-30
CY2024	dei	Entity Address Address Line1 EntityAddressAddressLine1	1800 Three Lincoln Centre
CY2024Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	1516000	usd
CY2023Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	3844000	usd
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CY2023Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1398000	usd
CY2023Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	92202000	usd
CY2023Q3	us-gaap	Goodwill Goodwill	731257000	usd
CY2023Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1201158000	usd
CY2023Q3	us-gaap	Assets Assets	22516968000	usd
CY2024Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.005
CY2023Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	200000000	shares
CY2024Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	155258845	shares
CY2024Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	155258845	shares
CY2023Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	148492783	shares
CY2023Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	148492783	shares
CY2023Q3	us-gaap	Common Stock Value CommonStockValue	742000	usd
CY2023Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	6684120000	usd
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CY2023Q3	ato	Securitized Long Term Debt Excluding Current Maturities SecuritizedLongTermDebtExcludingCurrentMaturities	85078000	usd
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CY2023Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	241933000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	1568000	usd
CY2023Q3	ato	Securitized Long Term Debt Current Maturities SecuritizedLongTermDebtCurrentMaturities	9922000	usd
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CY2023Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	2304974000	usd
CY2023Q3	ato	Change In Tax Rate Deferred Tax Liability ChangeInTaxRateDeferredTaxLiability	253212000	usd
CY2023Q3	ato	Regulatory Cost Of Removal Liability Noncurrent RegulatoryCostOfRemovalLiabilityNoncurrent	497017000	usd
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CY2024Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	25194465000	usd
CY2023Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	22516968000	usd
CY2022	us-gaap	Revenues Revenues	4201662000	usd
CY2024	ato	Cost Of Revenue Net CostOfRevenueNet	933693000	usd
CY2023	ato	Cost Of Revenue Net CostOfRevenueNet	1452173000	usd
CY2022	ato	Cost Of Revenue Net CostOfRevenueNet	1682656000	usd
CY2022	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	710161000	usd
CY2022	us-gaap	Depreciation And Amortization DepreciationAndAmortization	535655000	usd
CY2022	us-gaap	Taxes Other TaxesOther	352208000	usd
CY2022	us-gaap	Operating Income Loss OperatingIncomeLoss	920982000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	33737000	usd
CY2024	us-gaap	Interest Expense Nonoperating InterestExpenseNonoperating	190632000	usd
CY2023	us-gaap	Interest Expense Nonoperating InterestExpenseNonoperating	137281000	usd
CY2022	us-gaap	Interest Expense Nonoperating InterestExpenseNonoperating	102811000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	851908000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77510000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	774398000	usd
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.61
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.60
CY2024	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	152508000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	137830000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	138096000	shares
CY2022	us-gaap	Net Income Loss NetIncomeLoss	774398000	usd
CY2024	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	168000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-157000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	582000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-542000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	86664000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	299851000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	299309000	usd
CY2024	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	990082000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1073707000	usd
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CY2022	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.72
CY2022	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	375914000	usd
CY2022	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	776805000	usd
CY2022	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	7495000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	149416000	usd
CY2023	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	7966000	usd
CY2023	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2108000	usd
CY2023	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	21588000	usd
CY2023Q3	us-gaap	Stockholders Equity StockholdersEquity	10870064000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	1042895000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-52813000	usd
CY2024	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	3.22
CY2024	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	492950000	usd
CY2024	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	749987000	usd
CY2024	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	7129000	usd
CY2024	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	7955000	usd
CY2024	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2198000	usd
CY2024	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	23204000	usd
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CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	108215000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	53651000	usd
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CY2022	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	9141000	usd
CY2022	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	45505000	usd
CY2022	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-3265000	usd
CY2022	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	34325000	usd
CY2022	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	179825000	usd
CY2022	ato	Increase Decrease In Regulatory Assets Current IncreaseDecreaseInRegulatoryAssetsCurrent	0	usd
CY2022	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	65979000	usd
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CY2023	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-132575000	usd
CY2024	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-10287000	usd
CY2023	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	30687000	usd
CY2024	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	58701000	usd
CY2023	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	41788000	usd
CY2024	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1733746000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3459743000	usd
CY2024	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	2937124000	usd
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CY2023	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	46789000	usd
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CY2024	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	12050000	usd
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	13340000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	27586000	usd
CY2024	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-16062000	usd
CY2023	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-19008000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-10289000	usd
CY2024	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2922769000	usd
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2795280000	usd
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CY2023	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	56966000	usd
CY2024	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1240204000	usd
CY2023	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	797258000	usd
CY2024	ato	Proceeds From Issuance Of Securitized Long Term Debt ProceedsFromIssuanceOfSecuritizedLongTermDebt	0	usd
CY2023	ato	Proceeds From Issuance Of Securitized Long Term Debt ProceedsFromIssuanceOfSecuritizedLongTermDebt	95000000	usd
CY2024	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	749987000	usd
CY2023	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	806949000	usd
CY2024	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	15084000	usd
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CY2024	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	-231138000	usd
CY2023	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	-171145000	usd
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CY2023	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	2020000000	usd
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CY2024	ato	Repayments Of Long Term Securitized Debt RepaymentsOfLongTermSecuritizedDebt	9922000	usd
CY2023	ato	Repayments Of Long Term Securitized Debt RepaymentsOfLongTermSecuritizedDebt	0	usd
CY2022	ato	Repayments Of Long Term Securitized Debt RepaymentsOfLongTermSecuritizedDebt	0	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	430345000	usd
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CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1735000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1387205000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-65169000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	19248000	usd
CY2024Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	308856000	usd
CY2022Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	51554000	usd
CY2024	us-gaap	Nature Of Operations NatureOfOperations	Nature of Business<div style="margin-bottom:9pt;margin-top:5pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Atmos Energy Corporation (Atmos Energy or the “Company”) and its subsidiaries are engaged in the regulated natural gas distribution and pipeline and storage businesses. Through our distribution business, we deliver natural gas through sales and transportation arrangements to over 3.3 million residential, commercial, public-authority, and industrial customers through our six regulated distribution divisions in the service areas described below:</span></div><div><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.853%"><tr><td style="width:1.0%"></td><td style="width:47.069%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:2.560%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:47.071%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Service Area</span></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Atmos Energy Colorado-Kansas Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Colorado, Kansas</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Atmos Energy Kentucky/Mid-States Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Kentucky, Tennessee, Virginia</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Atmos Energy Louisiana Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Louisiana</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Atmos Energy Mid-Tex Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Texas, including the Dallas/Fort Worth metropolitan area</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Atmos Energy Mississippi Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Mississippi</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Atmos Energy West Texas Division</span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">West Texas</span></td></tr></table><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:6pt;font-weight:400;line-height:120%"> </span></div><div style="margin-top:4pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In addition, we transport natural gas for others through our distribution system. Our distribution business is subject to federal and state regulation and/or regulation by local authorities in each of the states in which our distribution divisions operate. Our corporate headquarters and shared-services function are located in Dallas, Texas, and our customer support centers are located in Amarillo and Waco, Texas.</span></div>Our pipeline and storage business, which is also subject to federal and state regulation, consists of the pipeline and storage operations of our Atmos Pipeline–Texas (APT) Division and our natural gas transmission business in Louisiana. The APT division provides transportation and storage services to our Mid-Tex Division, other third-party local distribution companies, industrial, and electric generation customers, as well as marketers and producers. As part of its pipeline operations, APT manages five underground storage facilities in Texas. We also provide ancillary services customary to the pipeline industry including parking arrangements, lending, and sales of inventory on hand. Our natural gas transmission operations in Louisiana are comprised of a 21-mile pipeline located in the New Orleans, Louisiana area that is primarily used to aggregate gas supply for our distribution division in Louisiana under a long-term contract and on a more limited basis, to third parties.
CY2024Q3	ato	Number Of Customers Regulated Distribution NumberOfCustomersRegulatedDistribution	3300000	customer
CY2024Q3	ato	Number Of Divisions Regulated Distribution NumberOfDivisionsRegulatedDistribution	6	regulateddistributiondivision
CY2024Q3	ato	Number Of Underground Storage Facilities NumberOfUndergroundStorageFacilities	5	facility
CY2024	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	Certain reclassifications have been made to prior period amounts to conform to current period presentation.
CY2024	us-gaap	Use Of Estimates UseOfEstimates	The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, and expenses. The most significant estimates include the allowance for doubtful accounts, unbilled revenues, contingency accruals, pension and postretirement obligations, deferred income taxes, risk management and trading activities, and fair value measurements. Actual results could differ from those estimates.
CY2024Q3	ato	Number Of Asset Management Plans Under Management NumberOfAssetManagementPlansUnderManagement	2	plan
CY2024	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	14655000	usd
CY2023	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	15808000	usd
CY2022	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	12153000	usd
CY2024	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	58234000	usd
CY2023	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	64019000	usd
CY2022	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	45505000	usd
CY2024	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	72889000	usd
CY2023	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	79827000	usd
CY2022	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	57658000	usd
CY2024	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.029
CY2023	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.03
CY2022	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.03
CY2024	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2022	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2023	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2024	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	We use financial instruments to mitigate commodity price risk in our distribution and pipeline and storage segments and to mitigate interest rate risk. The objectives and strategies for using financial instruments have been tailored to our business and are discussed in Note 16 to the consolidated financial statements.<div style="margin-top:5pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">We record all of our financial instruments on the balance sheet at fair value</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">,</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> with the exception of normal purchases and normal sales that are expected to result in physical delivery, with changes in fair value ultimately recorded in the statement of comprehensive income. These financial instruments are reported as risk management assets and liabilities and are classified as current or noncurrent other assets or liabilities based upon the anticipated settlement date of the underlying financial instrument. We record the cash flow impact of our financial instruments in operating cash flows based upon their balance sheet classification.</span></div><div style="margin-top:5pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The timing of when changes in fair value of our financial instruments are recorded in the statement of comprehensive income depends on whether the financial instrument has been designated and qualifies as a part of a hedging relationship or if regulatory rulings require a different accounting treatment. Changes in fair value for financial instruments that do not meet one of these criteria are recognized in the statement of comprehensive income as they occur.</span></div><div style="margin-top:6pt;text-indent:11.25pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments Associated with Commodity Price Risk</span></div><div style="margin-top:5pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In our distribution segment, the costs associated with and the realized gains and losses arising from the use of financial instruments to mitigate commodity price risk are included in our purchased gas cost adjustment mechanisms in accordance with regulatory requirements. Therefore, changes in the fair value of these financial instruments are initially recorded as a component of deferred gas costs and recognized in the consolidated statements of comprehensive income as a component of purchased gas cost when the related costs are recovered through our rates and recognized in revenue in accordance with accounting principles generally accepted in the United States. Accordingly, there is no earnings impact on our distribution segment as a result of the use of these financial instruments.</span></div><div style="margin-top:6pt;text-indent:11.25pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments Associated with Interest Rate Risk</span></div><div style="margin-top:5pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In connection with the planned issuance of long-term debt, we may use financial instruments to manage interest rate risk. We currently manage this risk through the use of forward starting interest rate swaps to fix the Treasury yield component of the interest cost associated with anticipated financings. We designate these financial instruments as cash flow hedges at the time the agreements are executed. Unrealized gains and losses associated with the instruments are recorded as a component of accumulated other comprehensive income (loss). When the instruments settle, the realized gain or loss is recorded as a component of accumulated other comprehensive income (loss) and recognized as a component of interest charges over the life of the related financing arrangement. As of September 30, 2024 and 2023, no cash was required to be held in margin accounts.</span></div>
CY2024Q3	ato	Derivative Cash Collateral DerivativeCashCollateral	0	usd
CY2023Q3	ato	Derivative Cash Collateral DerivativeCashCollateral	0	usd
CY2024	ato	Self Insured Retention Deductible SelfInsuredRetentionDeductible	1000000	usd
CY2024Q3	us-gaap	Regulatory Assets RegulatoryAssets	579390000	usd
CY2023Q3	us-gaap	Regulatory Assets RegulatoryAssets	554928000	usd
CY2024Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	1227882000	usd
CY2023Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	1284334000	usd
CY2024	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2024Q3	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	8	state
CY2024	us-gaap	Revenues Revenues	4165187000	usd
CY2024	us-gaap	Revenues Revenues	4165187000	usd
CY2024	ato	Cost Of Revenue Net CostOfRevenueNet	933693000	usd
CY2024	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	819137000	usd
CY2024	us-gaap	Depreciation And Amortization DepreciationAndAmortization	669972000	usd
CY2024	us-gaap	Taxes Other TaxesOther	387023000	usd
CY2024	us-gaap	Operating Income Loss OperatingIncomeLoss	1355362000	usd
CY2024	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	71046000	usd
CY2024	us-gaap	Interest Expense Nonoperating InterestExpenseNonoperating	190632000	usd
CY2024	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1235776000	usd
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	192881000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	1042895000	usd
CY2024	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	2937124000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2023	ato	Cost Of Revenue Net CostOfRevenueNet	1452173000	usd
CY2023	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	764906000	usd
CY2023	us-gaap	Depreciation And Amortization DepreciationAndAmortization	604327000	usd
CY2023	us-gaap	Taxes Other TaxesOther	386804000	usd
CY2023	us-gaap	Operating Income Loss OperatingIncomeLoss	1067147000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	69775000	usd
CY2023	us-gaap	Interest Expense Nonoperating InterestExpenseNonoperating	137281000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	999641000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113779000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
CY2023	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	2805973000	usd
CY2022	us-gaap	Revenues Revenues	4201662000	usd
CY2022	us-gaap	Revenues Revenues	4201662000	usd
CY2022	ato	Cost Of Revenue Net CostOfRevenueNet	1682656000	usd
CY2022	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	710161000	usd
CY2022	us-gaap	Depreciation And Amortization DepreciationAndAmortization	535655000	usd
CY2022	us-gaap	Taxes Other TaxesOther	352208000	usd
CY2022	us-gaap	Operating Income Loss OperatingIncomeLoss	920982000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	33737000	usd
CY2022	us-gaap	Interest Expense Nonoperating InterestExpenseNonoperating	102811000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	851908000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77510000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	774398000	usd
CY2022	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	2444420000	usd
CY2024	us-gaap	Revenues Revenues	4165187000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2022	us-gaap	Revenues Revenues	4201662000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	22204367000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	19606583000	usd
CY2023Q3	us-gaap	Assets Assets	22516968000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	1042895000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	774398000	usd
CY2024	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	553000	usd
CY2023	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	542000	usd
CY2022	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	508000	usd
CY2024	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1042342000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	885320000	usd
CY2024	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	152508000	shares
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	145121000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	137830000	shares
CY2024	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.83
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.10
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.61
CY2024	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1042342000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	885320000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	773890000	usd
CY2024	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	0	usd
CY2023	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	0	usd
CY2022	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	0	usd
CY2024	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	1042342000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	885320000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	773890000	usd
CY2024	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	152508000	shares
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	145121000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	137830000	shares
CY2024	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	158000	shares
CY2023	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	45000	shares
CY2022	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	266000	shares
CY2024	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	152666000	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	145166000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	138096000	shares
CY2024	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.83
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.10
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.60
CY2024Q3	ato	Number Of States With Ability To Recover Uncollectible Accounts Due To Gas Cost Recovery Mechanisms NumberOfStatesWithAbilityToRecoverUncollectibleAccountsDueToGasCostRecoveryMechanisms	6	state
CY2024	ato	Percent Of Customers With Ability To Recover Uncollectible Accounts Due To Gas Cost Recovery Mechanisms PercentOfCustomersWithAbilityToRecoverUncollectibleAccountsDueToGasCostRecoveryMechanisms	0.89
CY2021Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	64471000	usd
CY2022	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	16576000	usd
CY2022	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	32885000	usd
CY2022	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	1831000	usd
CY2022Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	49993000	usd
CY2023	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	22353000	usd
CY2023	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	33595000	usd
CY2023	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	2089000	usd
CY2023Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	40840000	usd
CY2024	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	24843000	usd
CY2024	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	26165000	usd
CY2024	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	1730000	usd
CY2024	ato	Accounts Receivable Allowance For Credit Loss Uncollectible Accounts That Are Not Yet Written Off AccountsReceivableAllowanceForCreditLossUncollectibleAccountsThatAreNotYetWrittenOff	4192000	usd
CY2024Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	37056000	usd
CY2024Q3	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P16Y8M12D
CY2023Q3	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P17Y8M12D
CY2024Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y10M24D
CY2023Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y1M6D
CY2024Q3	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.040
CY2023Q3	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.040
CY2024Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.041
CY2023Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.035
CY2024	ato	Finance Lease Cost FinanceLeaseCost	4523000	usd
CY2023	ato	Finance Lease Cost FinanceLeaseCost	4499000	usd
CY2022	ato	Finance Lease Cost FinanceLeaseCost	4314000	usd
CY2024	us-gaap	Operating Lease Cost OperatingLeaseCost	48421000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	44090000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	43394000	usd
CY2024	us-gaap	Lease Cost LeaseCost	52944000	usd
CY2023	us-gaap	Lease Cost LeaseCost	48589000	usd
CY2022	us-gaap	Lease Cost LeaseCost	47708000	usd
CY2024Q3	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	44748000	usd
CY2023Q3	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	47472000	usd
CY2024Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	249556000	usd
CY2023Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	223366000	usd
CY2024Q3	ato	Right Of Use Asset Finance Leaseand Operating Lease RightOfUseAssetFinanceLeaseandOperatingLease	294304000	usd
CY2023Q3	ato	Right Of Use Asset Finance Leaseand Operating Lease RightOfUseAssetFinanceLeaseandOperatingLease	270838000	usd
CY2024Q3	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1651000	usd
CY2023Q3	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1568000	usd
CY2024Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	34340000	usd
CY2023Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	35820000	usd
CY2024Q3	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	47239000	usd
CY2023Q3	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	48825000	usd
CY2024Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	224498000	usd
CY2023Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	194452000	usd
CY2024Q3	ato	Lease Liability LeaseLiability	307728000	usd
CY2023Q3	ato	Lease Liability LeaseLiability	280665000	usd
CY2024Q3	ato	Unrecorded Unconditional Purchase Obligation Number Of Buildings Leased UnrecordedUnconditionalPurchaseObligationNumberOfBuildingsLeased	2	servicecenter
CY2024Q3	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	93400000	usd
CY2024	us-gaap	Operating Lease Payments OperatingLeasePayments	47069000	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	45463000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	45080000	usd
CY2024	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	33833000	usd
CY2024	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	65672000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	29976000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	28310000	usd
CY2024Q3	ato	Lessee Liability Payments Due Next Rolling Twelve Months LesseeLiabilityPaymentsDueNextRollingTwelveMonths	46682000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due In Next Rolling Twelve Months FinanceLeaseLiabilityPaymentsDueInNextRollingTwelveMonths	3438000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due Next Rolling Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextRollingTwelveMonths	43244000	usd
CY2024Q3	ato	Lessee Liability Payments Due Next Rolling Two Years LesseeLiabilityPaymentsDueNextRollingTwoYears	42628000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Two FinanceLeaseLiabilityPaymentsDueInRollingYearTwo	3502000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Two LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearTwo	39126000	usd
CY2024Q3	ato	Lessee Liability Payments Due Next Rolling Three Years LesseeLiabilityPaymentsDueNextRollingThreeYears	38359000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Three FinanceLeaseLiabilityPaymentsDueInRollingYearThree	3568000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Three LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearThree	34791000	usd
CY2024Q3	ato	Lessee Liability Payments Due Next Rolling Four Years LesseeLiabilityPaymentsDueNextRollingFourYears	34553000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Four FinanceLeaseLiabilityPaymentsDueInRollingYearFour	3635000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Four LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearFour	30918000	usd
CY2024Q3	ato	Lessee Liability Payments Due Next Rolling Five Years LesseeLiabilityPaymentsDueNextRollingFiveYears	29204000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Five FinanceLeaseLiabilityPaymentsDueInRollingYearFive	3703000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Five LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearFive	25501000	usd
CY2024Q3	ato	Lessee Liability Payments Due After Rolling Five Years LesseeLiabilityPaymentsDueAfterRollingFiveYears	195488000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due In Rolling After Year Five FinanceLeaseLiabilityPaymentsDueInRollingAfterYearFive	48660000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Rolling Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterRollingYearFive	146828000	usd
CY2024Q3	ato	Lease Liability Lease Payments LeaseLiabilityLeasePayments	386914000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	66506000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	320408000	usd
CY2024Q3	ato	Lease Liability Imputed Interest LeaseLiabilityImputedInterest	79186000	usd
CY2024Q3	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	17616000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	61570000	usd
CY2024Q3	ato	Lease Liability LeaseLiability	307728000	usd
CY2024Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	48890000	usd
CY2024Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	258838000	usd
CY2024Q3	ato	Lease Liability Current LeaseLiabilityCurrent	35991000	usd
CY2024Q3	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1651000	usd
CY2024Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	34340000	usd
CY2024Q3	ato	Lease Liability Noncurrent LeaseLiabilityNoncurrent	271737000	usd
CY2024Q3	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	47239000	usd
CY2024Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	224498000	usd
CY2024Q3	ato	Lease Liability LeaseLiability	307728000	usd
CY2024Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	48890000	usd
CY2024Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	258838000	usd
CY2024Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	48890000	usd
CY2023Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	50393000	usd
CY2024Q3	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	7833890000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	6610393000	usd
CY2024Q3	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	-9071000	usd
CY2023Q3	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	6104000	usd
CY2024Q3	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	57664000	usd
CY2023Q3	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	48588000	usd
CY2024Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	1651000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	1568000	usd
CY2024Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	7783646000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	6554133000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	10000000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	500000000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	150000000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	500000000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	6625000000	usd
CY2024Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	7785000000	usd
CY2021Q1	us-gaap	Utilities Operating Expense Gas And Petroleum Purchased UtilitiesOperatingExpenseGasAndPetroleumPurchased	2300000000	usd
CY2024	us-gaap	Public Utilities Approved Debt Capital Structure Percentage PublicUtilitiesApprovedDebtCapitalStructurePercentage	0.70
CY2024Q3	us-gaap	Ratio Of Indebtedness To Net Capital1 RatioOfIndebtednessToNetCapital1	0.40
CY2024Q3	us-gaap	Forward Contract Indexed To Issuers Equity Settlement Alternatives Cash At Fair Value ForwardContractIndexedToIssuersEquitySettlementAlternativesCashAtFairValue	1400000000	usd
CY2024Q3	us-gaap	Forward Contract Indexed To Issuers Equity Settlement Alternatives Shares At Fair Value ForwardContractIndexedToIssuersEquitySettlementAlternativesSharesAtFairValue	11290120	shares
CY2024Q3	us-gaap	Forward Contract Indexed To Issuers Equity Settlement Alternatives Cash At Fair Value ForwardContractIndexedToIssuersEquitySettlementAlternativesCashAtFairValue	1380556000	usd
CY2024	us-gaap	Forward Contract Indexed To Issuers Equity Forward Rate ForwardContractIndexedToIssuersEquityForwardRate	122.28
CY2024	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-42848000	usd
CY2024	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	9965000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-52813000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	151536000	usd
CY2023	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	2120000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	149416000	usd
CY2024Q3	us-gaap	Remaining Recovery Period Of Regulatory Assets For Which No Return On Investment During Recovery Period Is Provided1 RemainingRecoveryPeriodOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided1	P15Y
CY2024	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	25400000	usd
CY2023	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	23700000	usd
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	22200000	usd
CY2024	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	14700000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	13500000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	11500000	usd
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	11200000	shares
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	400000	shares
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
CY2023Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	389957	shares
CY2023Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	109.10
CY2022Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	381295	shares
CY2022Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	105.69
CY2021Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	378127	shares
CY2021Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	102.45
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	212207	shares
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	117.11
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	241436	shares
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	109.78
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	179738	shares
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	108.07
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	201834	shares
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	108.56
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	220929	shares
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	104.05
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	159019	shares
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	100.99
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	2401	shares
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	115.44
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	11845	shares
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	107.47
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	17551	shares
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	103.37
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	397929	shares
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	113.78
CY2023Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	389957	shares
CY2023Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	109.10
CY2022Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	381295	shares
CY2022Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	105.69
CY2024Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	17600000	usd
CY2024	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y4M24D
CY2024	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	21600000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	22800000	usd
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	16000000.0	usd
CY2024Q3	ato	Minimum Initial Investment For Direct Stock Purchase Plan MinimumInitialInvestmentForDirectStockPurchasePlan	1250	usd
CY2024Q3	ato	Minimum Continuing Investment For Direct Stock Purchase Plan MinimumContinuingInvestmentForDirectStockPurchasePlan	25	usd
CY2024Q3	ato	Annual Maximum Investment For Direct Stock Purchase Plan AnnualMaximumInvestmentForDirectStockPurchasePlan	100000	usd
CY2024Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	402938000	usd
CY2023Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	369494000	usd
CY2024Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	37056000	usd
CY2023Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	40840000	usd
CY2024Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	365882000	usd
CY2023Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	328654000	usd
CY2024Q3	us-gaap	Deferred Gas Cost DeferredGasCost	159762000	usd
CY2023Q3	us-gaap	Deferred Gas Cost DeferredGasCost	148297000	usd
CY2024Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Current UnusualOrInfrequentEventsIncrementalCostsCapitalizedCurrent	3949000	usd
CY2023Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Current UnusualOrInfrequentEventsIncrementalCostsCapitalizedCurrent	21213000	usd
CY2024Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	74780000	usd
CY2023Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	58029000	usd
CY2024Q3	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	14332000	usd
CY2023Q3	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	13918000	usd
CY2024Q3	us-gaap	Supplies Supplies	16961000	usd
CY2023Q3	us-gaap	Supplies Supplies	34297000	usd
CY2024Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	2091000	usd
CY2023Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	4071000	usd
CY2024Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	16193000	usd
CY2023Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	12211000	usd
CY2024Q3	us-gaap	Other Assets Current OtherAssetsCurrent	288068000	usd
CY2023Q3	us-gaap	Other Assets Current OtherAssetsCurrent	292036000	usd
CY2024Q3	ato	Public Utilities Property Plantand Equipment Storage PublicUtilitiesPropertyPlantandEquipmentStorage	708617000	usd
CY2023Q3	ato	Public Utilities Property Plantand Equipment Storage PublicUtilitiesPropertyPlantandEquipmentStorage	668237000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	5713831000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	4995579000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	17304207000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	15283965000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Common PublicUtilitiesPropertyPlantAndEquipmentCommon	1019018000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Common PublicUtilitiesPropertyPlantAndEquipmentCommon	972054000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	38612000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	38612000	usd
CY2024Q3	ato	Public Utilities Property Plant And Equipment Plant In Service Excluding Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceExcludingConstructionWorkInProgress	24784285000	usd
CY2023Q3	ato	Public Utilities Property Plant And Equipment Plant In Service Excluding Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceExcludingConstructionWorkInProgress	21958447000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	1063798000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	939927000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	25848083000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	22898374000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3643716000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3291791000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	22204367000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	19606583000	usd
CY2024Q3	us-gaap	Public Utilities Property Plant And Equipment Amount Of Acquisition Adjustments1 PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1	-22900000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Amount Of Acquisition Adjustments1 PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1	-24800000	usd
CY2024Q3	us-gaap	Marketable Securities MarketableSecurities	110594000	usd
CY2023Q3	us-gaap	Marketable Securities MarketableSecurities	104602000	usd
CY2024Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	396958000	usd
CY2023Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	364741000	usd
CY2024Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	249556000	usd
CY2023Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	223366000	usd
CY2024Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Noncurrent UnusualOrInfrequentEventsIncrementalCostsCapitalizedNoncurrent	6424000	usd
CY2023Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Noncurrent UnusualOrInfrequentEventsIncrementalCostsCapitalizedNoncurrent	10902000	usd
CY2024Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	94197000	usd
CY2023Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	381593000	usd
CY2024Q3	us-gaap	Defined Benefit Plan Amounts Recognized In Balance Sheet DefinedBenefitPlanAmountsRecognizedInBalanceSheet	155611000	usd
CY2023Q3	us-gaap	Defined Benefit Plan Amounts Recognized In Balance Sheet DefinedBenefitPlanAmountsRecognizedInBalanceSheet	92648000	usd
CY2024Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	30343000	usd
CY2023Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	23306000	usd
CY2024Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1043683000	usd
CY2023Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1201158000	usd
CY2024Q3	us-gaap	Accounts Payable Current And Noncurrent AccountsPayableCurrentAndNoncurrent	341948000	usd
CY2023Q3	us-gaap	Accounts Payable Current And Noncurrent AccountsPayableCurrentAndNoncurrent	218181000	usd
CY2024Q3	ato	Accrued Gas Payable AccruedGasPayable	19125000	usd
CY2023Q3	ato	Accrued Gas Payable AccruedGasPayable	43688000	usd
CY2024Q3	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	84324000	usd
CY2023Q3	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	74214000	usd
CY2024Q3	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	445397000	usd
CY2023Q3	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	336083000	usd
CY2024Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	62085000	usd
CY2023Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	65266000	usd
CY2024Q3	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	64141000	usd
CY2023Q3	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	50042000	usd
CY2024Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	9142000	usd
CY2023Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	23093000	usd
CY2024Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	34340000	usd
CY2023Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	35820000	usd
CY2024Q3	us-gaap	Interest Payable Current InterestPayableCurrent	106116000	usd
CY2023Q3	us-gaap	Interest Payable Current InterestPayableCurrent	78939000	usd
CY2024Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	7324000	usd
CY2023Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	14584000	usd
CY2024Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	215857000	usd
CY2023Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	195468000	usd
CY2024Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	4622000	usd
CY2023Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	9375000	usd
CY2024Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	99217000	usd
CY2023Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	85850000	usd
CY2024Q3	ato	Regulatory Clause Revenues Over Recoveredcurrent RegulatoryClauseRevenuesOverRecoveredcurrent	35924000	usd
CY2023Q3	ato	Regulatory Clause Revenues Over Recoveredcurrent RegulatoryClauseRevenuesOverRecoveredcurrent	34550000	usd
CY2024Q3	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	79686000	usd
CY2023Q3	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	131301000	usd
CY2024Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	32166000	usd
CY2023Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	38798000	usd
CY2024Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	750620000	usd
CY2023Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	763086000	usd
CY2024Q3	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	67322000	usd
CY2023Q3	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	66523000	usd
CY2024Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	224498000	usd
CY2023Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	194452000	usd
CY2024Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	7973000	usd
CY2023Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	9158000	usd
CY2024Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	279979000	usd
CY2023Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	242049000	usd
CY2024Q3	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	7942000	usd
CY2023Q3	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	5174000	usd
CY2024Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	313000	usd
CY2023Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	824000	usd
CY2024Q3	ato	Regulatory Clause Revenues Over Recoveredlongterm RegulatoryClauseRevenuesOverRecoveredlongterm	37195000	usd
CY2023Q3	ato	Regulatory Clause Revenues Over Recoveredlongterm RegulatoryClauseRevenuesOverRecoveredlongterm	15344000	usd
CY2024Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	46174000	usd
CY2023Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	46620000	usd
CY2024Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	20536000	usd
CY2023Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	19754000	usd
CY2024Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	691932000	usd
CY2023Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	599898000	usd
CY2024	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	58234000	usd
CY2023	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	64019000	usd
CY2022	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	45505000	usd
CY2024	ato	Performance Based Rate Program Income Loss PerformanceBasedRateProgramIncomeLoss	8389000	usd
CY2023	ato	Performance Based Rate Program Income Loss PerformanceBasedRateProgramIncomeLoss	7093000	usd
CY2022	ato	Performance Based Rate Program Income Loss PerformanceBasedRateProgramIncomeLoss	8327000	usd
CY2024	ato	Pension And Other Postretirement Non Service Credit Cost PensionAndOtherPostretirementNonServiceCreditCost	10820000	usd
CY2023	ato	Pension And Other Postretirement Non Service Credit Cost PensionAndOtherPostretirementNonServiceCreditCost	8955000	usd
CY2022	ato	Pension And Other Postretirement Non Service Credit Cost PensionAndOtherPostretirementNonServiceCreditCost	8337000	usd
CY2024	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	22887000	usd
CY2023	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	7207000	usd
CY2022	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	2781000	usd
CY2024	ato	Charitable Contributions CharitableContributions	20016000	usd
CY2023	ato	Charitable Contributions CharitableContributions	12027000	usd
CY2022	ato	Charitable Contributions CharitableContributions	16357000	usd
CY2024	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	3562000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	1406000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-7737000	usd
CY2024	ato	Miscellaneous Non Operating Income Expense MiscellaneousNonOperatingIncomeExpense	-12830000	usd
CY2023	ato	Miscellaneous Non Operating Income Expense MiscellaneousNonOperatingIncomeExpense	-6878000	usd
CY2022	ato	Miscellaneous Non Operating Income Expense MiscellaneousNonOperatingIncomeExpense	-7119000	usd
CY2024	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	71046000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	69775000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	33737000	usd
CY2024	us-gaap	Interest Paid InterestPaid	308872000	usd
CY2023	us-gaap	Interest Paid InterestPaid	249066000	usd
CY2022	us-gaap	Interest Paid InterestPaid	234297000	usd
CY2024	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	15349000	usd
CY2023	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	14968000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	15760000	usd
CY2024	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	299908000	usd
CY2023	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	186912000	usd
CY2022	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	217868000	usd
CY2024	us-gaap	Interest Paid Net InterestPaidNet	163500000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	117900000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	98400000	usd
CY2024	ato	Long Term Purchase Commitment Purchases LongTermPurchaseCommitmentPurchases	105700000	usd
CY2023	ato	Long Term Purchase Commitment Purchases LongTermPurchaseCommitmentPurchases	182000000.0	usd
CY2022	ato	Long Term Purchase Commitment Purchases LongTermPurchaseCommitmentPurchases	352600000	usd
CY2024	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	5764000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-1274000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	2849000	usd
CY2024	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	13964000	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	13550000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	28125000	usd
CY2024	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	150244000	usd
CY2023	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	83244000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	43435000	usd
CY2024	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	22909000	usd
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	18259000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3101000	usd
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	192881000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113779000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77510000	usd
CY2024	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	259513000	usd
CY2023	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	209925000	usd
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	178901000	usd
CY2024	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1354000	usd
CY2023	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1355000	usd
CY2022	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1355000	usd
CY2024	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	29130000	usd
CY2023	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	25129000	usd
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	24669000	usd
CY2024	us-gaap	Income Tax Reconciliation Nondeductible Expense Amortization IncomeTaxReconciliationNondeductibleExpenseAmortization	-100271000	usd
CY2023	us-gaap	Income Tax Reconciliation Nondeductible Expense Amortization IncomeTaxReconciliationNondeductibleExpenseAmortization	-123953000	usd
CY2022	us-gaap	Income Tax Reconciliation Nondeductible Expense Amortization IncomeTaxReconciliationNondeductibleExpenseAmortization	-127193000	usd
CY2024	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	5863000	usd
CY2023	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	4033000	usd
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	2488000	usd
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	192881000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113779000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77510000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	41184000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	50576000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	484816000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	504121000	usd
CY2024Q3	ato	Deferred Tax Assets Charitable Contributionand Other Tax Credit Carryforwards DeferredTaxAssetsCharitableContributionandOtherTaxCreditCarryforwards	12301000	usd
CY2023Q3	ato	Deferred Tax Assets Charitable Contributionand Other Tax Credit Carryforwards DeferredTaxAssetsCharitableContributionandOtherTaxCreditCarryforwards	10084000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	46330000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	76943000	usd
CY2024Q3	ato	Deferred Tax Asset Lease DeferredTaxAssetLease	63747000	usd
CY2023Q3	ato	Deferred Tax Asset Lease DeferredTaxAssetLease	58633000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	34934000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	42257000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	683312000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	742614000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	1457000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	351000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	681855000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	742263000	usd
CY2024Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2914854000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2674341000	usd
CY2024Q3	ato	Deferred Tax Liability Gas Cost Adjustments DeferredTaxLiabilityGasCostAdjustments	49443000	usd
CY2023Q3	ato	Deferred Tax Liability Gas Cost Adjustments DeferredTaxLiabilityGasCostAdjustments	47822000	usd
CY2024Q3	ato	Deferred Liabilities Winter Storm Uri DeferredLiabilitiesWinterStormUri	20846000	usd
CY2023Q3	ato	Deferred Liabilities Winter Storm Uri DeferredLiabilitiesWinterStormUri	28116000	usd
CY2024Q3	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	57177000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	51666000	usd
CY2024Q3	ato	Deferred Tax Liability Rate Deferral Adjustment DeferredTaxLiabilityRateDeferralAdjustment	50571000	usd
CY2023Q3	ato	Deferred Tax Liability Rate Deferral Adjustment DeferredTaxLiabilityRateDeferralAdjustment	47218000	usd
CY2024Q3	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	134536000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	149969000	usd
CY2024Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	47770000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	48105000	usd
CY2024Q3	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	3275197000	usd
CY2023Q3	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	3047237000	usd
CY2024Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2593342000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2304974000	usd
CY2024Q3	us-gaap	Deferred Tax Assets Charitable Contribution Carryforwards DeferredTaxAssetsCharitableContributionCarryforwards	10200000	usd
CY2024Q3	ato	Deferred Tax Assets Operating Loss Carryforwards Domestic Impact State And Local DeferredTaxAssetsOperatingLossCarryforwardsDomesticImpactStateAndLocal	600000	usd
CY2024	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	57800000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	58600000	usd
CY2024Q3	ato	Unrecognized Tax Benefits Deferred Tax Liabilities UnrecognizedTaxBenefitsDeferredTaxLiabilities	11600000	usd
CY2023Q3	ato	Unrecognized Tax Benefits Deferred Tax Liabilities UnrecognizedTaxBenefitsDeferredTaxLiabilities	12000000	usd
CY2023Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	58638000	usd
CY2022Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	52683000	usd
CY2021Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	32792000	usd
CY2024	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	2867000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	631000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	721000	usd
CY2024	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	6188000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	usd
CY2024	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	8214000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	6586000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	20612000	usd
CY2024Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	57797000	usd
CY2023Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	58638000	usd
CY2022Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	52683000	usd
CY2024Q3	ato	Unrecognized Tax Benefits Deferred Federaland State Income Tax Benefits UnrecognizedTaxBenefitsDeferredFederalandStateIncomeTaxBenefits	12137000	usd
CY2023Q3	ato	Unrecognized Tax Benefits Deferred Federaland State Income Tax Benefits UnrecognizedTaxBenefitsDeferredFederalandStateIncomeTaxBenefits	12314000	usd
CY2022Q3	ato	Unrecognized Tax Benefits Deferred Federaland State Income Tax Benefits UnrecognizedTaxBenefitsDeferredFederalandStateIncomeTaxBenefits	11063000	usd
CY2024Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	45660000	usd
CY2023Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	46324000	usd
CY2022Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	41620000	usd
CY2024	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	100000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	3400000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	1300000	usd
CY2024Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	15100000	usd
CY2023Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	15100000	usd
CY2022Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	11700000	usd
CY2024	us-gaap	Derivative Nonmonetary Notional Amount Volume DerivativeNonmonetaryNotionalAmountVolume	26734	mmcf
CY2024Q3	us-gaap	Derivative Asset Fair Value Gross Liability And Obligation To Return Cash Offset DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset	0	usd
CY2023Q3	us-gaap	Derivative Asset Fair Value Gross Liability And Obligation To Return Cash Offset DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset	0	usd
CY2023Q3	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	0	usd
CY2024Q3	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	0	usd
CY2024Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	96288000	usd
CY2024Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	7637000	usd
CY2023Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	385664000	usd
CY2023Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	15408000	usd
CY2024	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	12800000	usd
CY2023	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	2700000	usd
CY2022	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-3800000	usd
CY2024	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	-43430000	usd
CY2023	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	151410000	usd
CY2024	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	-9965000	usd
CY2023	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	-2120000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-53395000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	149290000	usd
CY2024Q3	ato	Accumulated Other Comprehensive Income Loss Derivatives Qualifying As Hedges Interest Rate Agreements Realized Gain Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesInterestRateAgreementsRealizedGainLossNetOfTax	394100000	usd
CY2024Q3	us-gaap	Derivative Assets DerivativeAssets	96288000	usd
CY2023Q3	us-gaap	Derivative Assets DerivativeAssets	385664000	usd
CY2023Q3	ato	Debt And Equity Securities DebtAndEquitySecurities	104602000	usd
CY2023Q3	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	490266000	usd
CY2023Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	15408000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	usd
CY2024Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	38900000	usd
CY2023Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	36000000.0	usd
CY2024Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	7785000000	usd
CY2024Q3	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	7337936000	usd
CY2024Q3	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2024Q3	ecd	Rule10b51 Arr Adopted Flag Rule10b51ArrAdoptedFlag	false
CY2024Q3	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false
CY2024Q3	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false
CY2024	ecd	Insider Trd Policies Proc Adopted Flag InsiderTrdPoliciesProcAdoptedFlag	true

Files In Submission

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$ATO
ATMOS ENERGY CORP Stock $ato

2024 Q4 Form 10-K Financial Statement

#000073180224000030 Filed on November 18, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO ATMOS ENERGY CORP Stock $ato

2024 Q4 Form 10-K Financial Statement

#000073180224000030 Filed on November 18, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO
ATMOS ENERGY CORP Stock $ato