$ATO
ATMOS ENERGY CORP Stock $ato

$ato Overview Financials Valuation SEC Filings Company Website

2023 Q4 Form 10-K Financial Statement

#000073180223000028 Filed on November 14, 2023

Income Statement

Concept	2023 Q4	2023 Q3	2023
Revenue	$1.158B	$587.6M	$4.275B
YoY Change	-21.94%	-18.69%	1.75%
Cost Of Revenue	$338.9M	$3.200M	$1.452B
YoY Change	-54.1%	-98.32%	-13.7%
Gross Profit	$819.6M	$584.4M	$2.823B
YoY Change	9.9%	9.92%	12.08%
Gross Profit Margin	70.75%	99.46%	66.03%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$164.6M	$159.2M	$604.3M
YoY Change	12.73%	13.56%	12.82%
% of Gross Profit	20.08%	27.24%	21.41%
Operating Expenses	$420.5M	$430.4M	$1.756B
YoY Change	-0.96%	0.97%	9.89%
Operating Profit	$399.1M	$154.0M	$1.067B
YoY Change	24.26%	46.11%	15.87%
Interest Expense	$51.88M	-$31.80M	$137.3M
YoY Change	41.12%	14.22%	33.53%
% of Operating Profit	13.0%	-20.65%	12.86%
Other Income/Expense, Net	$17.89M	$15.00M	$69.78M
YoY Change	-15.6%	128.69%	106.82%
Pretax Income	$365.1M	$137.3M	$999.6M
YoY Change	19.47%	63.22%	17.34%
Income Tax	$53.82M	$18.70M	$113.8M
% Of Pretax Income	14.74%	13.62%	11.38%
Net Earnings	$311.3M	$118.5M	$885.9M
YoY Change	14.5%	65.4%	14.39%
Net Earnings / Revenue	26.87%	20.17%	20.72%
Basic Earnings Per Share	$2.08		$6.10
Diluted Earnings Per Share	$2.08	$0.80	$6.10
COMMON SHARES
Basic Shares Outstanding	148.5M shares	148.5M shares	145.1M shares
Diluted Shares Outstanding	149.8M shares		145.2M shares

Balance Sheet

Concept	2023 Q4	2023 Q3	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments	$278.3M	$120.0M	$15.00M
YoY Change	62.19%	-18.68%	-70.9%
Cash & Equivalents	$278.3M	$15.40M	$15.00M
Short-Term Investments		$104.6M
Other Short-Term Assets	$526.9M	$292.0M	$248.0M
YoY Change	-77.15%	-87.16%	-88.91%
Inventory	$220.9M	$246.0M	$280.0M
Prepaid Expenses		$58.03M
Receivables	$646.4M	$328.7M	$281.0M
Other Receivables	$0.00	$0.00	$62.00M
Total Short-Term Assets	$1.680B	$885.8M	$886.0M
YoY Change	-53.7%	-70.94%	-70.93%
LONG-TERM ASSETS
Property, Plant & Equipment	$20.32B	$19.61B	$19.83B
YoY Change	13.06%	13.73%	13.61%
Goodwill	$731.3M	$731.3M
YoY Change	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments			$105.0M
YoY Change			9.36%
Other Assets	$863.8M	$1.201B	$873.0M
YoY Change	-16.58%	2.33%	1.14%
Total Long-Term Assets	$22.00B	$21.63B	$21.63B
YoY Change	11.48%	12.98%	12.98%
TOTAL ASSETS
Total Short-Term Assets	$1.680B	$885.8M	$886.0M
Total Long-Term Assets	$22.00B	$21.63B	$21.63B
Total Assets	$23.68B	$22.52B	$22.52B
YoY Change	1.36%	1.46%	1.46%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$416.7M	$336.0M	$218.0M
YoY Change	-27.5%	-32.26%	-15.67%
Accrued Expenses			$283.0M
YoY Change			-26.18%
Deferred Revenue		$65.27M
YoY Change		16.51%
Short-Term Debt	$0.00	$241.9M	$242.0M
YoY Change		30.8%	30.83%
Long-Term Debt Due	$11.48M	$11.00M	$11.00M
YoY Change	-99.48%	-99.5%	-99.5%
Total Short-Term Liabilities	$1.170B	$1.353B	$1.353B
YoY Change	-66.86%	-62.46%	-62.44%
LONG-TERM LIABILITIES
Long-Term Debt	$7.529B	$6.639B	$6.639B
YoY Change	14.92%	15.25%	15.25%
Other Long-Term Liabilities	$601.7M	$599.9M	$1.350B
YoY Change	13.5%	11.44%	-4.33%
Total Long-Term Liabilities	$601.7M	$599.9M	$7.989B
YoY Change	13.5%	11.44%	11.39%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.170B	$1.353B	$1.353B
Total Long-Term Liabilities	$601.7M	$599.9M	$7.989B
Total Liabilities	$1.772B	$1.952B	$11.65B
YoY Change	-56.37%	-52.85%	-8.82%
SHAREHOLDERS EQUITY
Retained Earnings	$3.858B	$3.667B
YoY Change	14.2%	14.19%
Common Stock	$6.947B	$6.685B
YoY Change	14.51%	14.49%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$11.27B	$10.87B	$10.87B
YoY Change
Total Liabilities & Shareholders Equity	$23.68B	$22.52B	$22.52B
YoY Change	1.36%	1.46%	1.46%

Cashflow Statement

Concept	2023 Q4	2023 Q3	2023
OPERATING ACTIVITIES
Net Income	$311.3M	$118.5M	$885.9M
YoY Change	14.5%	65.4%	14.39%
Depreciation, Depletion And Amortization	$164.6M	$159.2M	$604.3M
YoY Change	12.73%	13.56%	12.82%
Cash From Operating Activities	$245.3M	$238.2M	$3.460B
YoY Change	29.85%	393.49%	253.91%
INVESTING ACTIVITIES
Capital Expenditures	$769.7M	$722.5M	$2.806B
YoY Change	-3.27%	-200.57%	-214.79%
Acquisitions
YoY Change
Other Investing Activities	-$5.353M	$4.500M	-$19.01M
YoY Change	-4.77%	50.4%	84.74%
Cash From Investing Activities	-$764.4M	-$718.0M	-$2.795B
YoY Change	-3.55%	0.36%	15.03%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$806.9M
YoY Change			3.88%
Debt Paid & Issued, Net			$2.200B
YoY Change			1000.0%
Cash From Financing Activities	$785.3M	440.8M	-$696.8M
YoY Change	8.52%	12.85%	-150.23%
NET CHANGE
Cash From Operating Activities	$245.3M	238.2M	$3.460B
Cash From Investing Activities	-$764.4M	-718.0M	-$2.795B
Cash From Financing Activities	$785.3M	440.8M	-$696.8M
Net Change In Cash	$266.2M	-39.00M	-$32.31M
YoY Change	121.75%	-85.9%	-50.43%
FREE CASH FLOW
Cash From Operating Activities	$245.3M	$238.2M	$3.460B
Capital Expenditures	$769.7M	$722.5M	$2.806B
Free Cash Flow	-$524.4M	-$484.3M	$653.7M
YoY Change	-13.58%	-163.17%	-80.9%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2022Q3	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#LongTermDebtAndCapitalLeaseObligationsCurrent
CY2022Q3	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#PublicUtilitiesPropertyPlantAndEquipmentNet
CY2023Q3	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#PublicUtilitiesPropertyPlantAndEquipmentNet
CY2022Q3	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2023Q3	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2023Q3	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#LongTermDebtAndCapitalLeaseObligationsCurrent
CY2023Q3	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2022Q3	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2023Q3	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#LongTermDebtAndCapitalLeaseObligations
CY2022Q3	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#LongTermDebtAndCapitalLeaseObligations
CY2023Q3	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2022Q3	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2023	dei	Document Period End Date DocumentPeriodEndDate	2023-09-30
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--09-30
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
CY2022Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.005
CY2023Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	200000000	shares
CY2023Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	148492783	shares
CY2023Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	148492783	shares
CY2022Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	140896598	shares
CY2022Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	140896598	shares
CY2023Q3	us-gaap	Common Stock Value CommonStockValue	742000	usd
CY2023Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	6684120000	usd
CY2023Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	518528000	usd
CY2023Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	3666674000	usd
CY2023Q3	us-gaap	Stockholders Equity StockholdersEquity	10870064000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	6554133000	usd
CY2023Q3	ato	Securitized Long Term Debt Excluding Current Maturities SecuritizedLongTermDebtExcludingCurrentMaturities	85078000	usd
CY2023Q3	us-gaap	Capitalization Longterm Debt And Equity CapitalizationLongtermDebtAndEquity	17509275000	usd
CY2023Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2023Q3	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	336083000	usd
CY2023Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	763086000	usd
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
CY2023Q3	us-gaap	Liabilities Current LiabilitiesCurrent	1352592000	usd
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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CY2023Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	22516968000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	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 InterestExpense	137281000	usd
CY2022	us-gaap	Interest Expense InterestExpense	102811000	usd
CY2021	us-gaap	Interest Expense InterestExpense	83554000	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
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CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.10
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.10
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	145121000	shares
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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
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	43148000	usd
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CY2021	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	606667000	usd
CY2021	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	7715000	usd
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CY2023	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-46859000	usd
CY2023	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-112111000	usd
CY2023	ato	Increase Decrease In Regulatory Assets Current IncreaseDecreaseInRegulatoryAssetsCurrent	-2021889000	usd
CY2023	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	36041000	usd
CY2023	ato	Increase Decrease In Regulatory Assets Noncurrent IncreaseDecreaseInRegulatoryAssetsNoncurrent	0	usd
CY2022	ato	Increase Decrease In Regulatory Assets Noncurrent IncreaseDecreaseInRegulatoryAssetsNoncurrent	0	usd
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CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2797346000	usd
CY2022	ato	Proceeds From Issuance Of Securitized Long Term Debt ProceedsFromIssuanceOfSecuritizedLongTermDebt	0	usd
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CY2021	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	606667000	usd
CY2022	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	15403000	usd
CY2021	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	15841000	usd
CY2022	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	-197073000	usd
CY2021	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	-62159000	usd
CY2022	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	usd
CY2021	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	usd
CY2022	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	usd
CY2021	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	200000000	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	430345000	usd
CY2023	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	7864000	usd
CY2023	ato	Payments Of Securitized Debt Issuance Costs PaymentsOfSecuritizedDebtIssuanceCosts	1273000	usd
CY2023	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-696769000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-32306000	usd
CY2022Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	51554000	usd
CY2023	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.
CY2023Q3	ato	Number Of Customers Regulated Distribution NumberOfCustomersRegulatedDistribution	3300000	customer
CY2023Q3	ato	Number Of Divisions Regulated Distribution NumberOfDivisionsRegulatedDistribution	6	regulateddistributiondivision
CY2023Q3	ato	Number Of Underground Storage Facilities NumberOfUndergroundStorageFacilities	5	facility
CY2023	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Reclassification</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> — Certain reclassifications have been made to prior period amounts to conform to current period presentation.</span>
CY2023	us-gaap	Use Of Estimates UseOfEstimates	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of estimates</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> — 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.</span>
CY2023Q3	ato	Number Of Asset Management Plans Under Management NumberOfAssetManagementPlansUnderManagement	2	plan
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
CY2021	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	11414000	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
CY2021	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	32749000	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
CY2021	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	44163000	usd
CY2022	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.03
CY2023	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.03
CY2021	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.03
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
CY2021	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2023	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	<div style="margin-top:5pt;text-indent:24.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Financial instruments and hedging activities</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> — 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.</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%">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, 2023 and 2022, no cash was required to be held in margin accounts.</span></div>
CY2023Q3	ato	Derivative Cash Collateral DerivativeCashCollateral	0	usd
CY2022Q3	ato	Derivative Cash Collateral DerivativeCashCollateral	0	usd
CY2023	ato	Self Insured Retention Deductible SelfInsuredRetentionDeductible	1000000	usd
CY2023Q3	us-gaap	Regulatory Assets RegulatoryAssets	554928000	usd
CY2022Q3	us-gaap	Regulatory Assets RegulatoryAssets	2605372000	usd
CY2023Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	1284334000	usd
CY2022Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	1353170000	usd
CY2023	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2023Q3	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	8	state
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2023	us-gaap	Cost Of Revenue CostOfRevenue	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 InterestExpense	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	us-gaap	Cost Of Revenue CostOfRevenue	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 InterestExpense	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
CY2021	us-gaap	Revenues Revenues	3407490000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	665098000	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
CY2021	us-gaap	Revenues Revenues	3407490000	usd
CY2021	us-gaap	Cost Of Revenue CostOfRevenue	1032717000	usd
CY2021	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	679019000	usd
CY2021	us-gaap	Depreciation And Amortization DepreciationAndAmortization	477977000	usd
CY2021	us-gaap	Taxes Other TaxesOther	312779000	usd
CY2021	us-gaap	Operating Income Loss OperatingIncomeLoss	904998000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-2145000	usd
CY2021	us-gaap	Interest Expense InterestExpense	83554000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	819299000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	153736000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	665563000	usd
CY2021	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1969540000	usd
CY2023	us-gaap	Revenues Revenues	4275357000	usd
CY2022	us-gaap	Revenues Revenues	4201662000	usd
CY2021	us-gaap	Revenues Revenues	3407490000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	19606583000	usd
CY2023Q3	us-gaap	Assets Assets	22516968000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	885862000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	774398000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	665563000	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
CY2021	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	465000	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
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	665098000	usd
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
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	129779000	shares
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.10
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.61
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.12
CY2021	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	0	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
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	665098000	usd
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
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	129779000	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
CY2021	us-gaap	Incremental Common Shares Attributable To Equity Forward Agreements IncrementalCommonSharesAttributableToEquityForwardAgreements	55000	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
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	129834000	shares
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.10
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.60
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.12
CY2023Q3	ato	Number Of States With Ability To Recover Uncollectible Accounts Due To Gas Cost Recovery Mechanisms NumberOfStatesWithAbilityToRecoverUncollectibleAccountsDueToGasCostRecoveryMechanisms	5	state
CY2023	ato	Percent Of Customers With Ability To Recover Uncollectible Accounts Due To Gas Cost Recovery Mechanisms PercentOfCustomersWithAbilityToRecoverUncollectibleAccountsDueToGasCostRecoveryMechanisms	0.80
CY2020Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	29949000	usd
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	43807000	usd
CY2021	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	11019000	usd
CY2021	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	1734000	usd
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
CY2023Q3	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P17Y8M12D
CY2022Q3	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P18Y8M12D
CY2023Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y1M6D
CY2022Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y8M12D
CY2023Q3	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.040
CY2022Q3	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.040
CY2023Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.035
CY2022Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.029
CY2023	ato	Finance Lease Cost FinanceLeaseCost	4499000	usd
CY2022	ato	Finance Lease Cost FinanceLeaseCost	4314000	usd
CY2021	ato	Finance Lease Cost FinanceLeaseCost	1334000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	44090000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	43394000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	42349000	usd
CY2023	us-gaap	Lease Cost LeaseCost	48589000	usd
CY2022	us-gaap	Lease Cost LeaseCost	47708000	usd
CY2021	us-gaap	Lease Cost LeaseCost	43683000	usd
CY2023Q3	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	47472000	usd
CY2022Q3	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	50118000	usd
CY2023Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	223366000	usd
CY2022Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	214663000	usd
CY2023Q3	ato	Right Of Use Asset Finance Leaseand Operating Lease RightOfUseAssetFinanceLeaseandOperatingLease	270838000	usd
CY2022Q3	ato	Right Of Use Asset Finance Leaseand Operating Lease RightOfUseAssetFinanceLeaseandOperatingLease	264781000	usd
CY2023Q3	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1568000	usd
CY2022Q3	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1457000	usd
CY2023Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	35820000	usd
CY2022Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	38644000	usd
CY2023Q3	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	48825000	usd
CY2022Q3	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	50393000	usd
CY2023Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	194452000	usd
CY2022Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	184301000	usd
CY2023Q3	ato	Lease Liability LeaseLiability	280665000	usd
CY2022Q3	ato	Lease Liability LeaseLiability	274795000	usd
CY2023Q3	ato	Lessee Not Yet Commenced Number Of Buildings Leased LesseeNotYetCommencedNumberOfBuildingsLeased	1	servicecenter
CY2023Q3	ato	Lessee Not Yet Commenced Future Payments LesseeNotYetCommencedFuturePayments	28900000	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	45463000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	45080000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	42013000	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
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	10333000	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
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	25690000	usd
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
CY2020Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	443279	shares
CY2020Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	99.28
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	241436	shares
CY2023Q3	ato	Lessee Liability Payments Due Next Rolling Twelve Months LesseeLiabilityPaymentsDueNextRollingTwelveMonths	44700000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due In Next Rolling Twelve Months FinanceLeaseLiabilityPaymentsDueInNextRollingTwelveMonths	3375000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due Next Rolling Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextRollingTwelveMonths	41325000	usd
CY2023Q3	ato	Lessee Liability Payments Due Next Rolling Two Years LesseeLiabilityPaymentsDueNextRollingTwoYears	35635000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Two FinanceLeaseLiabilityPaymentsDueInRollingYearTwo	3438000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Two LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearTwo	32197000	usd
CY2023Q3	ato	Lessee Liability Payments Due Next Rolling Three Years LesseeLiabilityPaymentsDueNextRollingThreeYears	30340000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Three FinanceLeaseLiabilityPaymentsDueInRollingYearThree	3502000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Three LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearThree	26838000	usd
CY2023Q3	ato	Lessee Liability Payments Due Next Rolling Four Years LesseeLiabilityPaymentsDueNextRollingFourYears	27835000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Four FinanceLeaseLiabilityPaymentsDueInRollingYearFour	3568000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Four LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearFour	24267000	usd
CY2023Q3	ato	Lessee Liability Payments Due Next Rolling Five Years LesseeLiabilityPaymentsDueNextRollingFiveYears	24089000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due In Rolling Year Five FinanceLeaseLiabilityPaymentsDueInRollingYearFive	3635000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due In Rolling Year Five LesseeOperatingLeaseLiabilityPaymentsDueInRollingYearFive	20454000	usd
CY2023Q3	ato	Lessee Liability Payments Due After Rolling Five Years LesseeLiabilityPaymentsDueAfterRollingFiveYears	185270000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due In Rolling After Year Five FinanceLeaseLiabilityPaymentsDueInRollingAfterYearFive	52362000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Rolling Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterRollingYearFive	132908000	usd
CY2023Q3	ato	Lease Liability Lease Payments LeaseLiabilityLeasePayments	347869000	usd
CY2023Q3	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	69880000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	277989000	usd
CY2023Q3	ato	Lease Liability Imputed Interest LeaseLiabilityImputedInterest	67204000	usd
CY2023Q3	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	19487000	usd
CY2023Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	47717000	usd
CY2023Q3	ato	Lease Liability LeaseLiability	280665000	usd
CY2023Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	50393000	usd
CY2023Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	230272000	usd
CY2023Q3	ato	Lease Liability Current LeaseLiabilityCurrent	37388000	usd
CY2023Q3	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1568000	usd
CY2023Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	35820000	usd
CY2023Q3	ato	Lease Liability Noncurrent LeaseLiabilityNoncurrent	243277000	usd
CY2023Q3	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	48825000	usd
CY2023Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	194452000	usd
CY2023Q3	ato	Lease Liability LeaseLiability	280665000	usd
CY2023Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	50393000	usd
CY2023Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	230272000	usd
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
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	223954	shares
CY2021	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	102.68
CY2023Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	50393000	usd
CY2022Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	51850000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	6610393000	usd
CY2022Q3	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	8011850000	usd
CY2023Q3	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	6104000	usd
CY2022Q3	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	3704000	usd
CY2023Q3	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	48588000	usd
CY2022Q3	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	46042000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	1568000	usd
CY2022Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	2201457000	usd
CY2023Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	6554133000	usd
CY2022Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	5760647000	usd
CY2023Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	usd
CY2023Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	usd
CY2023Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	10000000	usd
CY2023Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	500000000	usd
CY2023Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	150000000	usd
CY2023Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	5900000000	usd
CY2023Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	6560000000	usd
CY2021Q1	us-gaap	Utilities Operating Expense Gas And Petroleum Purchased UtilitiesOperatingExpenseGasAndPetroleumPurchased	2300000000	usd
CY2023	us-gaap	Public Utilities Approved Debt Capital Structure Percentage PublicUtilitiesApprovedDebtCapitalStructurePercentage	0.70
CY2023Q3	us-gaap	Ratio Of Indebtedness To Net Capital1 RatioOfIndebtednessToNetCapital1	0.40
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
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	271435	shares
CY2021	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	97.44
CY2023Q3	us-gaap	Forward Contract Indexed To Issuers Equity Settlement Alternatives Cash At Fair Value ForwardContractIndexedToIssuersEquitySettlementAlternativesCashAtFairValue	466800000	usd
CY2023Q3	us-gaap	Forward Contract Indexed To Issuers Equity Settlement Alternatives Shares At Fair Value ForwardContractIndexedToIssuersEquitySettlementAlternativesSharesAtFairValue	3961025	shares
CY2023Q3	us-gaap	Forward Contract Indexed To Issuers Equity Settlement Alternatives Cash At Fair Value ForwardContractIndexedToIssuersEquitySettlementAlternativesCashAtFairValue	466803000	usd
CY2023	us-gaap	Forward Contract Indexed To Issuers Equity Forward Rate ForwardContractIndexedToIssuersEquityForwardRate	117.85
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 OtherComprehensiveIncomeLossNetOfTax	149416000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	296333000	usd
CY2022	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-2976000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	299309000	usd
CY2023Q3	us-gaap	Remaining Recovery Period Of Regulatory Assets For Which No Return On Investment During Recovery Period Is Provided1 RemainingRecoveryPeriodOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided1	P15Y
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
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	17671	shares
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	101.48
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
CY2023	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	23700000	usd
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	22200000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	24100000	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
CY2021	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	12900000	usd
CY2023Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	11200000	shares
CY2023Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	600000	shares
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y
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
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
CY2023Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	13900000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y4M24D
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	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	26300000	usd
CY2023Q3	ato	Minimum Initial Investment For Direct Stock Purchase Plan MinimumInitialInvestmentForDirectStockPurchasePlan	1250	usd
CY2023Q3	ato	Minimum Continuing Investment For Direct Stock Purchase Plan MinimumContinuingInvestmentForDirectStockPurchasePlan	25	usd
CY2023Q3	ato	Annual Maximum Investment For Direct Stock Purchase Plan AnnualMaximumInvestmentForDirectStockPurchasePlan	100000	usd
CY2023Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	369494000	usd
CY2022Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	413701000	usd
CY2023Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	40840000	usd
CY2022Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	49993000	usd
CY2023Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	328654000	usd
CY2022Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	363708000	usd
CY2023Q3	us-gaap	Deferred Gas Cost DeferredGasCost	148297000	usd
CY2022Q3	us-gaap	Deferred Gas Cost DeferredGasCost	119742000	usd
CY2023Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Current UnusualOrInfrequentEventsIncrementalCostsCapitalizedCurrent	21213000	usd
CY2022Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Current UnusualOrInfrequentEventsIncrementalCostsCapitalizedCurrent	2020954000	usd
CY2023Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	58029000	usd
CY2022Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	58551000	usd
CY2023Q3	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	13918000	usd
CY2022Q3	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	11911000	usd
CY2023Q3	us-gaap	Supplies Supplies	34297000	usd
CY2022Q3	us-gaap	Supplies Supplies	25880000	usd
CY2023Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	4071000	usd
CY2022Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	26207000	usd
CY2023Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	12211000	usd
CY2022Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	11245000	usd
CY2023Q3	us-gaap	Other Assets Current OtherAssetsCurrent	292036000	usd
CY2022Q3	us-gaap	Other Assets Current OtherAssetsCurrent	2274490000	usd
CY2023Q3	us-gaap	Defined Benefit Plan Amounts Recognized In Balance Sheet DefinedBenefitPlanAmountsRecognizedInBalanceSheet	92648000	usd
CY2023Q3	ato	Public Utilities Property Plantand Equipment Storage PublicUtilitiesPropertyPlantandEquipmentStorage	668237000	usd
CY2022Q3	ato	Public Utilities Property Plantand Equipment Storage PublicUtilitiesPropertyPlantandEquipmentStorage	589210000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	4995579000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	4325540000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	15283965000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	13511409000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Common PublicUtilitiesPropertyPlantAndEquipmentCommon	972054000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Common PublicUtilitiesPropertyPlantAndEquipmentCommon	937500000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	38612000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	38612000	usd
CY2023Q3	ato	Public Utilities Property Plant And Equipment Plant In Service Excluding Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceExcludingConstructionWorkInProgress	21958447000	usd
CY2022Q3	ato	Public Utilities Property Plant And Equipment Plant In Service Excluding Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceExcludingConstructionWorkInProgress	19402271000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	939927000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	835868000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	22898374000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	20238139000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3291791000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	2997900000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	19606583000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	17240239000	usd
CY2023Q3	us-gaap	Public Utilities Property Plant And Equipment Amount Of Acquisition Adjustments1 PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1	-24800000	usd
CY2022Q3	us-gaap	Public Utilities Property Plant And Equipment Amount Of Acquisition Adjustments1 PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1	-26600000	usd
CY2023Q3	us-gaap	Marketable Securities MarketableSecurities	104602000	usd
CY2022Q3	us-gaap	Marketable Securities MarketableSecurities	96012000	usd
CY2023Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	364741000	usd
CY2022Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	368375000	usd
CY2023Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	223366000	usd
CY2022Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	214663000	usd
CY2023Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Noncurrent UnusualOrInfrequentEventsIncrementalCostsCapitalizedNoncurrent	10902000	usd
CY2022Q3	ato	Unusual Or Infrequent Events Incremental Costs Capitalized Noncurrent UnusualOrInfrequentEventsIncrementalCostsCapitalizedNoncurrent	88500000	usd
CY2023Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	381593000	usd
CY2022Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	355784000	usd
CY2022Q3	us-gaap	Defined Benefit Plan Amounts Recognized In Balance Sheet DefinedBenefitPlanAmountsRecognizedInBalanceSheet	29498000	usd
CY2023Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	23306000	usd
CY2022Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	20968000	usd
CY2023Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1201158000	usd
CY2022Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1173800000	usd
CY2023Q3	us-gaap	Accounts Payable Current And Noncurrent AccountsPayableCurrentAndNoncurrent	218181000	usd
CY2022Q3	us-gaap	Accounts Payable Current And Noncurrent AccountsPayableCurrentAndNoncurrent	258506000	usd
CY2023Q3	ato	Accrued Gas Payable AccruedGasPayable	43688000	usd
CY2022Q3	ato	Accrued Gas Payable AccruedGasPayable	157942000	usd
CY2023Q3	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	74214000	usd
CY2022Q3	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	79571000	usd
CY2023Q3	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	336083000	usd
CY2022Q3	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	496019000	usd
CY2023Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	65266000	usd
CY2022Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	56016000	usd
CY2023Q3	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	50042000	usd
CY2022Q3	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	47661000	usd
CY2023Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	23093000	usd
CY2022Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	28834000	usd
CY2023Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	35820000	usd
CY2022Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	38644000	usd
CY2023Q3	us-gaap	Interest Payable Current InterestPayableCurrent	78939000	usd
CY2022Q3	us-gaap	Interest Payable Current InterestPayableCurrent	59542000	usd
CY2023Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	14584000	usd
CY2022Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	3000000	usd
CY2023Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	195468000	usd
CY2022Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	189239000	usd
CY2023Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	9375000	usd
CY2022Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	9721000	usd
CY2023Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	85850000	usd
CY2022Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	80676000	usd
CY2023Q3	ato	Regulatory Clause Revenues Over Recoveredcurrent RegulatoryClauseRevenuesOverRecoveredcurrent	34550000	usd
CY2022Q3	ato	Regulatory Clause Revenues Over Recoveredcurrent RegulatoryClauseRevenuesOverRecoveredcurrent	18034000	usd
CY2023Q3	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	131301000	usd
CY2022Q3	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	159808000	usd
CY2023Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	38798000	usd
CY2022Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	28982000	usd
CY2023Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	763086000	usd
CY2022Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	720157000	usd
CY2023Q3	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	66523000	usd
CY2022Q3	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	91596000	usd
CY2023Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	194452000	usd
CY2022Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	184301000	usd
CY2023Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	9158000	usd
CY2022Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	8628000	usd
CY2023Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	242049000	usd
CY2022Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	178990000	usd
CY2023Q3	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	5174000	usd
CY2022Q3	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	5737000	usd
CY2023Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	824000	usd
CY2022Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	1129000	usd
CY2023Q3	ato	Regulatory Clause Revenues Over Recoveredlongterm RegulatoryClauseRevenuesOverRecoveredlongterm	15344000	usd
CY2022Q3	ato	Regulatory Clause Revenues Over Recoveredlongterm RegulatoryClauseRevenuesOverRecoveredlongterm	13104000	usd
CY2023Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	46620000	usd
CY2022Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	39908000	usd
CY2023Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	19754000	usd
CY2022Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	14909000	usd
CY2023Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	599898000	usd
CY2022Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	538302000	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
CY2021	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	32749000	usd
CY2023	ato	Performance Based Rate Program Income Loss PerformanceBasedRateProgramIncomeLoss	7093000	usd
CY2022	ato	Performance Based Rate Program Income Loss PerformanceBasedRateProgramIncomeLoss	8327000	usd
CY2021	ato	Performance Based Rate Program Income Loss PerformanceBasedRateProgramIncomeLoss	6362000	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
CY2021	ato	Pension And Other Postretirement Non Service Credit Cost PensionAndOtherPostretirementNonServiceCreditCost	-19238000	usd
CY2023	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	7207000	usd
CY2022	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	2781000	usd
CY2021	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	2144000	usd
CY2023	ato	Charitable Contributions CharitableContributions	12027000	usd
CY2022	ato	Charitable Contributions CharitableContributions	16357000	usd
CY2021	ato	Charitable Contributions CharitableContributions	14460000	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
CY2021	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-860000	usd
CY2023	ato	Miscellaneous Non Operating Income Expense MiscellaneousNonOperatingIncomeExpense	-6878000	usd
CY2022	ato	Miscellaneous Non Operating Income Expense MiscellaneousNonOperatingIncomeExpense	-7119000	usd
CY2021	ato	Miscellaneous Non Operating Income Expense MiscellaneousNonOperatingIncomeExpense	-8842000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	69775000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	33737000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-2145000	usd
CY2023	us-gaap	Interest Paid InterestPaid	249066000	usd
CY2022	us-gaap	Interest Paid InterestPaid	234297000	usd
CY2021	us-gaap	Interest Paid InterestPaid	207555000	usd
CY2023	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	14968000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	15760000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	8199000	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
CY2021	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	184786000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	117900000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	98400000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	81900000	usd
CY2023	ato	Long Term Purchase Commitment Purchases LongTermPurchaseCommitmentPurchases	182000000	usd
CY2022	ato	Long Term Purchase Commitment Purchases LongTermPurchaseCommitmentPurchases	352600000	usd
CY2021	ato	Long Term Purchase Commitment Purchases LongTermPurchaseCommitmentPurchases	149400000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-1274000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	2849000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	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
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	252000	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
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	128867000	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
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	24617000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113779000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77510000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	153736000	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
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	172053000	usd
CY2023	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1355000	usd
CY2022	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1355000	usd
CY2021	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1372000	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
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	19647000	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
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Amortization IncomeTaxReconciliationNondeductibleExpenseAmortization	-45382000	usd
CY2023	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	4033000	usd
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	2488000	usd
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	8790000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113779000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77510000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	153736000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	50576000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	57094000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	504121000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	485061000	usd
CY2023Q3	ato	Deferred Tax Assets Charitable Contributionand Other Tax Credit Carryforwards DeferredTaxAssetsCharitableContributionandOtherTaxCreditCarryforwards	10084000	usd
CY2022Q3	ato	Deferred Tax Assets Charitable Contributionand Other Tax Credit Carryforwards DeferredTaxAssetsCharitableContributionandOtherTaxCreditCarryforwards	1903000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	76943000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	110548000	usd
CY2023Q3	ato	Deferred Tax Asset Lease DeferredTaxAssetLease	58633000	usd
CY2022Q3	ato	Deferred Tax Asset Lease DeferredTaxAssetLease	50007000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	42257000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	44035000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	742614000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	748648000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	351000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	523000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	742263000	usd
CY2022Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	748125000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2674341000	usd
CY2022Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2431757000	usd
CY2023Q3	ato	Deferred Tax Liability Gas Cost Adjustments DeferredTaxLiabilityGasCostAdjustments	47822000	usd
CY2022Q3	ato	Deferred Tax Liability Gas Cost Adjustments DeferredTaxLiabilityGasCostAdjustments	43964000	usd
CY2023Q3	ato	Deferred Liabilities Winter Storm Uri DeferredLiabilitiesWinterStormUri	28116000	usd
CY2022Q3	ato	Deferred Liabilities Winter Storm Uri DeferredLiabilitiesWinterStormUri	20710000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	51666000	usd
CY2022Q3	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	50007000	usd
CY2023Q3	ato	Deferred Tax Liability Rate Deferral Adjustment DeferredTaxLiabilityRateDeferralAdjustment	47218000	usd
CY2022Q3	ato	Deferred Tax Liability Rate Deferral Adjustment DeferredTaxLiabilityRateDeferralAdjustment	49309000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	149969000	usd
CY2022Q3	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	106820000	usd
CY2023Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	48105000	usd
CY2022Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	45063000	usd
CY2023Q3	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	3047237000	usd
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CY2022Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1999505000	usd
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CY2022Q3	ato	Unrecognized Tax Benefits Deferred Tax Liabilities UnrecognizedTaxBenefitsDeferredTaxLiabilities	12800000	usd
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CY2021Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	32792000	usd
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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
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	671000	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
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1200000	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
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
CY2021Q3	ato	Unrecognized Tax Benefits Deferred Federaland State Income Tax Benefits UnrecognizedTaxBenefitsDeferredFederalandStateIncomeTaxBenefits	6886000	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
CY2021Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	25906000	usd
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CY2021	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	1400000	usd
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CY2022Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	11700000	usd
CY2021Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	10400000	usd
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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
CY2022Q3	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	0	usd
CY2023Q3	ato	Derivative Asset Netof Contract Netting DerivativeAssetNetofContractNetting	385664000	usd
CY2023Q3	ato	Derivative Liability Netof Contract Netting DerivativeLiabilityNetofContractNetting	15408000	usd
CY2022Q3	ato	Derivative Asset Netof Contract Netting DerivativeAssetNetofContractNetting	381991000	usd
CY2022Q3	ato	Derivative Liability Netof Contract Netting DerivativeLiabilityNetofContractNetting	4129000	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
CY2023	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	151410000	usd
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CY2023	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	-2120000	usd
CY2022	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	2976000	usd
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CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	299851000	usd
CY2023Q3	ato	Accumulated Other Comprehensive Income Loss Derivatives Qualifying As Hedges Interest Rate Agreements Realized Gain Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesInterestRateAgreementsRealizedGainLossNetOfTax	224800000	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
CY2023Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	usd
CY2023Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	36000000	usd
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CY2023Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	6560000000	usd
CY2023Q3	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	5402591000	usd

Files In Submission

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$ATO
ATMOS ENERGY CORP Stock $ato

2023 Q4 Form 10-K Financial Statement

#000073180223000028 Filed on November 14, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO ATMOS ENERGY CORP Stock $ato

2023 Q4 Form 10-K Financial Statement

#000073180223000028 Filed on November 14, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO
ATMOS ENERGY CORP Stock $ato