$ATO
Atmos Energy Corp Stock $ato

$ato Overview Financials Valuation SEC Filings Company Website

2013 Form 10-K Financial Statement

#000073180213000017 Filed on November 13, 2013

Income Statement

Concept	2013	2012 Q3	2012 Q2
Revenue	$3.875B	$552.6M	$576.4M
YoY Change	12.78%	-29.13%	-30.82%
Cost Of Revenue	$2.463B	$300.9M	$19.53M
YoY Change	16.62%	-45.01%	-96.61%
Gross Profit	$1.412B	$249.4M	$293.2M
YoY Change	6.67%	5.16%	12.06%
Gross Profit Margin	36.44%	45.13%	50.86%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$236.9M	$62.20M	$61.40M
YoY Change	-3.74%	1.14%	5.14%
% of Gross Profit	16.78%	24.94%	20.94%
Operating Expenses	$910.2M	$221.3M	$211.6M
YoY Change	3.72%	10.26%	-9.07%
Operating Profit	$501.9M	$22.79M	$81.55M
YoY Change	12.47%	-41.85%	159.75%
Interest Expense	$128.4M	-$33.90M	$34.91M
YoY Change	-9.06%	-11.26%	-2.61%
% of Operating Profit	25.58%	-148.74%	42.81%
Other Income/Expense, Net	-$197.0K	-$11.10M	-$2.075M
YoY Change	-98.65%	344.0%	45.1%
Pretax Income	$373.3M	-$22.20M	$44.56M
YoY Change	28.54%	-3800.0%	-1493.87%
Income Tax	$142.6M	-$21.90M	$16.55M
% Of Pretax Income	38.2%		37.13%
Net Earnings	$243.2M	$7.967M	$31.13M
YoY Change	12.22%	306.27%	-5600.35%
Net Earnings / Revenue	6.28%	1.44%	5.4%
Basic Earnings Per Share	$2.68	$0.09	$0.34
Diluted Earnings Per Share	$2.64	$0.09	$0.34
COMMON SHARES
Basic Shares Outstanding	90.53M shares	90.17M shares	90.12M shares
Diluted Shares Outstanding	91.71M shares		90.99M shares

Balance Sheet

Concept	2013	2012 Q3	2012 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$66.00M	$128.6M	$28.00M
YoY Change	3.13%	-30.11%	-76.07%
Cash & Equivalents	$66.00M	$64.24M	$27.71M
Short-Term Investments		$64.40M
Other Short-Term Assets	$56.00M	$272.8M	$291.9M
YoY Change	-78.87%	-13.81%	6.73%
Inventory	$250.0M	$256.0M	$239.0M
Prepaid Expenses		$17.11M
Receivables	$269.0M	$234.5M	$216.8M
Other Receivables	$36.00M	$0.00	$0.00
Total Short-Term Assets	$677.0M	$828.0M	$775.7M
YoY Change	-18.24%	-18.1%	-21.63%
LONG-TERM ASSETS
Property, Plant & Equipment	$6.031B	$5.476B	$5.442B
YoY Change	10.14%	6.37%	10.7%
Goodwill		$740.7M
YoY Change		0.09%
Intangibles
YoY Change
Long-Term Investments	$73.00M
YoY Change	14.06%
Other Assets	$412.0M	$451.3M	$392.1M
YoY Change	6.46%	17.58%	12.68%
Total Long-Term Assets	$7.257B	$6.668B	$6.574B
YoY Change	8.83%	6.31%	9.5%
TOTAL ASSETS
Total Short-Term Assets	$677.0M	$828.0M	$775.7M
Total Long-Term Assets	$7.257B	$6.668B	$6.574B
Total Assets	$7.934B	$7.496B	$7.350B
YoY Change	5.84%	2.92%	5.1%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$70.00M	$215.0M	$178.0M
YoY Change	-67.44%	-26.12%	-42.95%
Accrued Expenses	$262.0M
YoY Change	263.89%
Deferred Revenue
YoY Change
Short-Term Debt	$368.0M	$570.9M	$213.5M
YoY Change	-35.55%	176.62%
Long-Term Debt Due		$131.0K	$250.1M
YoY Change		-94.62%	10176.54%
Total Short-Term Liabilities	$978.0M	$1.276B	$1.110B
YoY Change	-23.35%	47.07%	71.26%
LONG-TERM LIABILITIES
Long-Term Debt	$2.456B	$1.956B	$1.956B
YoY Change	25.56%	-11.32%	-11.32%
Other Long-Term Liabilities	$756.0M	$50.73M	$460.9M
YoY Change	-14.96%	-91.02%	4.89%
Total Long-Term Liabilities	$3.212B	$2.007B	$2.417B
YoY Change	12.9%	-27.57%	-8.63%
TOTAL LIABILITIES
Total Short-Term Liabilities	$978.0M	$1.276B	$1.110B
Total Long-Term Liabilities	$3.212B	$2.007B	$2.417B
Total Liabilities	$5.354B	$3.283B	$3.527B
YoY Change	4.24%	-9.77%	7.09%
SHAREHOLDERS EQUITY
Retained Earnings		$660.9M	$684.9M
YoY Change		15.85%	14.25%
Common Stock		$1.746B	$1.737B
YoY Change		0.72%	0.4%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.580B	$2.359B	$2.355B
YoY Change
Total Liabilities & Shareholders Equity	$7.934B	$7.496B	$7.350B
YoY Change	5.84%	2.92%	5.1%

Cashflow Statement

Concept	2013	2012 Q3	2012 Q2
OPERATING ACTIVITIES
Net Income	$243.2M	$7.967M	$31.13M
YoY Change	12.22%	306.27%	-5600.35%
Depreciation, Depletion And Amortization	$236.9M	$62.20M	$61.40M
YoY Change	-3.74%	1.14%	5.14%
Cash From Operating Activities	$613.1M	$68.10M	$158.1M
YoY Change	4.47%	7.75%	94.94%
INVESTING ACTIVITIES
Capital Expenditures	-$845.0M	-$235.5M	-$186.3M
YoY Change	15.3%	1.2%	29.74%
Acquisitions
YoY Change
Other Investing Activities	$4.904M	$127.8M	-$300.0K
YoY Change	6.03%	-12880.0%	-84.21%
Cash From Investing Activities	-$696.9M	-$107.7M	-$186.6M
YoY Change	14.39%	-53.92%	28.25%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net	$0.00
YoY Change
Debt Paid & Issued, Net	$131.0K
YoY Change	-99.95%
Cash From Financing Activities	$85.75M	76.10M	9.200M
YoY Change	-291.24%	-58.73%	-67.83%
NET CHANGE
Cash From Operating Activities	$613.1M	68.10M	158.1M
Cash From Investing Activities	-$696.9M	-107.7M	-186.6M
Cash From Financing Activities	$85.75M	76.10M	9.200M
Net Change In Cash	$1.960M	36.50M	-19.30M
YoY Change	-102.92%	162.59%	-46.09%
FREE CASH FLOW
Cash From Operating Activities	$613.1M	$68.10M	$158.1M
Capital Expenditures	-$845.0M	-$235.5M	-$186.3M
Free Cash Flow	$1.458B	$303.6M	$344.4M
YoY Change	10.48%	2.6%	53.27%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2012Q3	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	215229000	USD
CY2012Q3	us-gaap	Accounts Payable Current And Noncurrent AccountsPayableCurrentAndNoncurrent	82531000	USD
CY2013Q3	us-gaap	Accounts Payable Current And Noncurrent AccountsPayableCurrentAndNoncurrent	70116000	USD
CY2013Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	322616000	USD
CY2013	us-gaap	Accelerated Share Repurchases Final Price Paid Per Share AcceleratedShareRepurchasesFinalPricePaidPerShare	29.99
CY2012Q3	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	215229000	USD
CY2013Q3	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	241611000	USD
CY2012Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	243951000	USD
CY2012Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	234526000	USD
CY2013Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	301992000	USD
CY2013Q3	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	54034000	USD
CY2012Q3	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	37675000	USD
CY2012Q3	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	51040000	USD
CY2013Q3	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	50293000	USD
CY2012Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1658866000	USD
CY2013Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1691364000	USD
CY2013Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	38878000	USD
CY2012Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-47607000	USD
CY2013Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	1765811000	USD
CY2012Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	1745467000	USD
CY2011	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11600000	USD
CY2013	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	17800000	USD
CY2012	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	19200000	USD
CY2012Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	9425000	USD
CY2013Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	20624000	USD
CY2012	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	8147000	USD
CY2011	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	9438000	USD
CY2013	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	8480000	USD
CY2012	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	500000	USD
CY2013	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	500000	USD
CY2011	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	500000	USD
CY2011	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	4000	USD
CY2012	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	4000	USD
CY2013	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	5000	USD
CY2011	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2013	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
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CY2012Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	200000000	shares
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CY2012Q3	us-gaap	Common Stock Value CommonStockValue	451000	USD
CY2013	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	329679000	USD
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CY2012	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	217570000	USD
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CY2012	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	631000	USD
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CY2013Q3	us-gaap	Customer Advances For Construction CustomerAdvancesForConstruction	11723000	USD
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CY2012Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Other DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsOther	48513000	USD
CY2013Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Other DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsOther	52051000	USD
CY2012Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	62802000	USD
CY2013Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	63919000	USD
CY2013Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	11496000	USD
CY2012Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	7906000	USD
CY2013Q3	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	2271000	USD
CY2012Q3	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	2342000	USD
CY2013Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	1100000	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1519768000	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1311381000	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities Current DeferredTaxLiabilitiesCurrent	14697000	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities Current DeferredTaxLiabilitiesCurrent	0	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	2815000	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	2065000	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities Financing Arrangements DeferredTaxLiabilitiesFinancingArrangements	21726000	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities Financing Arrangements DeferredTaxLiabilitiesFinancingArrangements	0	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	0	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	7115000	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1254698000	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1445450000	USD
CY2012Q3	us-gaap	Deferred Tax Liabilities Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssets	21806000	USD
CY2013Q3	us-gaap	Deferred Tax Liabilities Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssets	19182000	USD
CY2011	us-gaap	Depreciation And Amortization DepreciationAndAmortization	223832000	USD
CY2012	us-gaap	Depreciation And Amortization DepreciationAndAmortization	237525000	USD
CY2013	us-gaap	Depreciation And Amortization DepreciationAndAmortization	235079000	USD
CY2013Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	18099000	USD
CY2012Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	24707000	USD
CY2012Q3	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	-67597000	USD
CY2013Q3	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	119777000	USD
CY2013Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	109354000	USD
CY2012Q3	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	2283000	USD
CY2012Q3	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	-91383000	USD
CY2013Q3	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	94948000	USD
CY2013Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	1543000	USD
CY2012Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	85381000	USD
CY2013Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	6133000	USD
CY2012Q3	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	9206000	USD
CY2013	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;">Financial instruments and hedging activities</font><font style="font-family:inherit;font-size:10pt;"> — We use financial instruments to mitigate commodity price risk in our natural gas distribution and nonregulated segments and interest rate risk. The objectives and strategies for using financial instruments have been tailored to our regulated and nonregulated businesses and are discussed in Note 12.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We record all of our financial instruments on the balance sheet at fair value</font><font style="font-family:inherit;font-size:10pt;font-style:italic;">,</font><font style="font-family:inherit;font-size:10pt;"> with changes in fair value ultimately recorded in the income statement. 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.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The timing of when changes in fair value of our financial instruments are recorded in the income statement 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 income statement as they occur.</font></div><div style="line-height:120%;padding-top:12px;text-indent:16px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-style:italic;">Financial Instruments Associated with Commodity Price Risk</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In our natural gas distribution segment, the costs associated with and the 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 statement of 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 natural gas distribution segment as a result of the use of financial instruments.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In our nonregulated segment, we have designated most of the natural gas inventory held by this operating segment as the hedged item in a fair-value hedge. This inventory is marked to market at the end of each month based on the Gas Daily index, with changes in fair value recognized as unrealized gains or losses in revenue in the period of change. The financial instruments associated with this natural gas inventory have been designated as fair-value hedges and are marked to market each month based upon the NYMEX price with changes in fair value recognized as unrealized gains or losses in revenue in the period of change. We have elected to exclude this spot/forward differential for purposes of assessing the effectiveness of these fair-value hedges. </font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Additionally, we have elected to treat fixed-price forward contracts used in our nonregulated segment to deliver natural gas as normal purchases and normal sales. As such, these deliveries are recorded on an accrual basis in accordance with our revenue recognition policy. Financial instruments used to mitigate the commodity price risk associated with these contracts have been designated as cash flow hedges of anticipated purchases and sales at indexed prices. Accordingly, unrealized gains and losses on these open financial instruments are recorded as a component of accumulated other comprehensive income, and are recognized in earnings as a component of revenue when the hedged volumes are sold.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Gains and losses from hedge ineffectiveness are recognized in the income statement. Fair value and cash flow hedge ineffectiveness arising from natural gas market price differences between the locations of the hedged inventory and the delivery location specified in the financial instruments is referred to as basis ineffectiveness. Ineffectiveness arising from changes in the fair value of the fair value hedges due to changes in the difference between the spot price and the futures price, as well as the difference between the timing of the settlement of the futures and the valuation of the underlying physical commodity is referred to as timing ineffectiveness. Hedge ineffectiveness, to the extent incurred, is reported as a component of revenue.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our nonregulated segment also utilizes master netting agreements with significant counterparties that allow us to offset gains and losses arising from financial instruments that may be settled in cash with gains and losses arising from financial instruments that may be settled with the physical commodity. Assets and liabilities from risk management activities, as well as accounts receivable and payable, reflect the master netting agreements in place. Additionally, the accounting guidance for master netting arrangements requires us to include the fair value of cash collateral or the obligation to return cash in the amounts that have been netted under master netting agreements used to offset gains and losses arising from financial instruments. As of </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">September 30, 2013</font><font style="font-family:inherit;font-size:10pt;"> and </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">2012</font><font style="font-family:inherit;font-size:10pt;">, the Company netted $</font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">24.8 million</font><font style="font-family:inherit;font-size:10pt;"> and $</font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">23.7 million</font><font style="font-family:inherit;font-size:10pt;"> of cash held in margin accounts into its current risk management assets and liabilities.</font></div><div style="line-height:120%;padding-top:12px;text-indent:16px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-style:italic;">Financial Instruments Associated with Interest Rate Risk</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We manage interest rate risk, typically when we plan to issue new long-term debt or to refinance existing long-term debt. Prior to fiscal 2012, we entered into Treasury lock agreements to fix the Treasury yield component of the interest cost associated with anticipated financings. We designated these Treasury lock agreements as cash flow hedges at the time the agreements were executed. Accordingly, unrealized gains and losses associated with the Treasury lock agreements were recorded as a component of accumulated other comprehensive income (loss). When the Treasury locks were settled, the realized gain or loss was recorded as a component of accumulated other comprehensive income (loss) and is being recognized as a component of interest expense over the life of the related financing arrangement.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">During fiscal 2012, we began using interest rate swaps and forward starting interest rate swaps to mitigate interest rate risk. Unrealized gains and losses associated with the swaps are recorded as a component of accumulated other comprehensive income (loss). When the swaps settle, the realized gain or loss will be recorded as a component of accumulated other comprehensive income (loss) and recognized as a component of interest expense over the life of the related financing arrangement. Hedge ineffectiveness to the extent incurred will be reported as a component of interest expense.</font></div></div>
CY2012	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	9868000	USD
CY2011	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	0	USD
CY2013	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	8203000	USD
CY2012	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	6349000	USD
CY2011	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2013	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	5294000	USD
CY2013Q1	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2013Q3	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2012Q4	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2013Q2	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	5294000	USD
CY2012Q2	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2012Q3	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	6349000	USD
CY2011Q4	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2012Q1	us-gaap	Discontinued Operation Gain Loss On Disposal Of Discontinued Operation Net Of Tax DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax	0	USD
CY2013	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	11188000	USD
CY2012	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	28238000	USD
CY2011	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	30385000	USD
CY2013	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	7202000	USD
CY2011	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	18013000	USD
CY2012	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	18172000	USD
CY2012Q4	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	3117000	USD
CY2013Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	0	USD
CY2013Q1	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	4085000	USD
CY2013Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	0	USD
CY2011Q4	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	6123000	USD
CY2012Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	1904000	USD
CY2012Q1	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	7027000	USD
CY2012Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Net Of Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax	3118000	USD
CY2011	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Discontinued Operation During Phase Out Period DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod	12372000	USD
CY2012	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Discontinued Operation During Phase Out Period DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod	10066000	USD
CY2013	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Discontinued Operation During Phase Out Period DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod	3986000	USD
CY2012	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Disposal Of Discontinued Operation DiscontinuedOperationTaxEffectOfIncomeLossFromDisposalOfDiscontinuedOperation	3519000	USD
CY2011	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Disposal Of Discontinued Operation DiscontinuedOperationTaxEffectOfIncomeLossFromDisposalOfDiscontinuedOperation	0	USD
CY2013	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Disposal Of Discontinued Operation DiscontinuedOperationTaxEffectOfIncomeLossFromDisposalOfDiscontinuedOperation	2909000	USD
CY2012Q3	us-gaap	Disposal Group Including Discontinued Operation Accounts Payable DisposalGroupIncludingDiscontinuedOperationAccountsPayable	2114000	USD
CY2013	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	5858000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	24174000	USD
CY2011	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	27362000	USD
CY2013	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	10640000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	27627000	USD
CY2011	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	30328000	USD
CY2012Q3	us-gaap	Disposal Group Including Discontinued Operation Other Current Assets DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets	6931000	USD
CY2012Q3	us-gaap	Disposal Group Including Discontinued Operation Other Current Liabilities DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities	3776000	USD
CY2012Q3	us-gaap	Disposal Group Including Discontinued Operation Other Noncurrent Assets DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentAssets	87000	USD
CY2012Q3	us-gaap	Disposal Group Including Discontinued Operation Other Noncurrent Liabilities DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities	2426000	USD
CY2012Q3	us-gaap	Disposal Group Including Discontinued Operation Property Plant And Equipment Net DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNet	142865000	USD
CY2013	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	128115000	USD
CY2012	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	125796000	USD
CY2011	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	124011000	USD
CY2011	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.28
CY2013	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.68
CY2012	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.39
CY2013Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.08
CY2012Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.89
CY2013Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.28
CY2013Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.43
CY2012Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.09
CY2012Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.20
CY2011Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.75
CY2012Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.34
CY2013	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.64
CY2012	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.37
CY2011	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.27
CY2013Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.27
CY2013Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.08
CY2012Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.88
CY2013Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.42
CY2012Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.20
CY2012Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.34
CY2011Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
CY2012Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.09
CY2013Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	5100000	USD
CY2013	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y7M6D
CY2012Q3	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	256415000	USD
CY2013Q3	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	244741000	USD
CY2013Q3	us-gaap	Financial Instruments Owned At Fair Value FinancialInstrumentsOwnedAtFairValue	127453000	USD
CY2012Q3	us-gaap	Financial Instruments Owned At Fair Value FinancialInstrumentsOwnedAtFairValue	27138000	USD
CY2013	us-gaap	Finite Lived Intangible Asset Useful Life FiniteLivedIntangibleAssetUsefulLife	P10Y
CY2013Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	121000	USD
CY2012Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	164000	USD
CY2011	us-gaap	Gain Loss On Cash Flow Hedge Ineffectiveness Net GainLossOnCashFlowHedgeIneffectivenessNet	-1585000	USD
CY2013	us-gaap	Gain Loss On Cash Flow Hedge Ineffectiveness Net GainLossOnCashFlowHedgeIneffectivenessNet	97000	USD
CY2012	us-gaap	Gain Loss On Cash Flow Hedge Ineffectiveness Net GainLossOnCashFlowHedgeIneffectivenessNet	-1369000	USD
CY2012	us-gaap	Gain Loss On Fair Value Hedges Recognized In Earnings GainLossOnFairValueHedgesRecognizedInEarnings	24469000	USD
CY2011	us-gaap	Gain Loss On Fair Value Hedges Recognized In Earnings GainLossOnFairValueHedgesRecognizedInEarnings	26376000	USD
CY2013	us-gaap	Gain Loss On Fair Value Hedges Recognized In Earnings GainLossOnFairValueHedgesRecognizedInEarnings	18103000	USD
CY2013Q3	us-gaap	Goodwill Goodwill	741363000	USD
CY2012Q3	us-gaap	Goodwill Goodwill	740683000	USD
CY2013	us-gaap	Goodwill Other Changes GoodwillOtherChanges	680000	USD
CY2013	us-gaap	Gross Profit GrossProfit	1412050000	USD
CY2012	us-gaap	Gross Profit GrossProfit	1323739000	USD
CY2011	us-gaap	Gross Profit GrossProfit	1300820000	USD
CY2012Q4	us-gaap	Gross Profit GrossProfit	362362000	USD
CY2013Q2	us-gaap	Gross Profit GrossProfit	316497000	USD
CY2013Q1	us-gaap	Gross Profit GrossProfit	432751000	USD
CY2013Q3	us-gaap	Gross Profit GrossProfit	300440000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	189588000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	192196000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	230698000	USD
CY2011Q4	us-gaap	Gross Profit GrossProfit	355392000	USD
CY2012Q2	us-gaap	Gross Profit GrossProfit	293171000	USD
CY2012Q1	us-gaap	Gross Profit GrossProfit	425787000	USD
CY2012Q3	us-gaap	Gross Profit GrossProfit	249389000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	373297000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	290422000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	296407000	USD
CY2013Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	7536000	USD
CY2013Q1	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	112340000	USD
CY2013Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	33474000	USD
CY2012Q4	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	77348000	USD
CY2012Q1	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	102084000	USD
CY2012Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	28014000	USD
CY2012Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-286000	USD
CY2011Q4	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	62384000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.08
CY2013	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.54
CY2012	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.12
CY2013Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.08
CY2013Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.24
CY2013Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.37
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.85
CY2011Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.68
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.31
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.00
CY2012Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.12
CY2013	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.50
CY2011	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.07
CY2012	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.10
CY2013Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.08
CY2013Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.36
CY2013Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.23
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.85
CY2011Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.68
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.00
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.31
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.04
CY2012Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.12
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	12496000	USD
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	18013000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	24521000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.27
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.20
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.14
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.06
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.04
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.00
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.04
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.09
CY2011Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.07
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.03
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.08
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.20
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.14
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.27
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.06
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.03
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.08
CY2011Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.07
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.09
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.03
CY2013	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	142599000	USD
CY2012	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98226000	USD
CY2011	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	106819000	USD
CY2013Q3	us-gaap	Income Tax Receivable IncomeTaxReceivable	3141000	USD
CY2012Q3	us-gaap	Income Tax Receivable IncomeTaxReceivable	1291000	USD
CY2011	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1930000	USD
CY2013	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	2153000	USD
CY2012	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	2096000	USD
CY2011	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	103743000	USD
CY2012	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	101648000	USD
CY2013	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	130655000	USD
CY2012	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	66000	USD
CY2011	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	2292000	USD
CY2013	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	153000	USD
CY2011	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-445000	USD
CY2012	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	2735000	USD
CY2013	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1916000	USD
CY2011	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	8109000	USD
CY2013	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	10687000	USD
CY2012	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-5958000	USD
CY2013	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	1341000	USD
CY2011	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	-4950000	USD
CY2012	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	1831000	USD
CY2013	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	10008000	USD
CY2012	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-432000	USD
CY2011	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-8329000	USD
CY2012	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-64234000	USD
CY2013	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	31912000	USD
CY2011	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	23904000	USD
CY2013	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	73669000	USD
CY2012	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-32578000	USD
CY2011	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	96000	USD
CY2012	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-28417000	USD
CY2013	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-31979000	USD
CY2011	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-27737000	USD
CY2013	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-15644000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-20989000	USD
CY2011	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	38048000	USD
CY2011	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-57495000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	7889000	USD
CY2013	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-44491000	USD
CY2013	us-gaap	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights	1178000	shares
CY2012	us-gaap	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights	1022000	shares
CY2011	us-gaap	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights	451000	shares
CY2012	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2600000	USD
CY2013	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	1900000	USD
CY2011	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	1700000	USD
CY2012	us-gaap	Interest Expense InterestExpense	141174000	USD
CY2013	us-gaap	Interest Expense InterestExpense	128385000	USD
CY2011	us-gaap	Interest Expense InterestExpense	150763000	USD
CY2011	us-gaap	Interest Paid InterestPaid	157976000	USD
CY2013	us-gaap	Interest Paid InterestPaid	148461000	USD
CY2012	us-gaap	Interest Paid InterestPaid	150606000	USD
CY2013Q3	us-gaap	Interest Payable Current InterestPayableCurrent	36744000	USD
CY2012Q3	us-gaap	Interest Payable Current InterestPayableCurrent	34451000	USD
CY2011	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-2455000	USD
CY2013	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-3489000	USD
CY2012	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-2009000	USD
CY2013	us-gaap	Net Income Loss NetIncomeLoss	243194000	USD
CY2011	us-gaap	Net Income Loss NetIncomeLoss	207601000	USD
CY2013	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-696914000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-609260000	USD
CY2013	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	613127000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	582844000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	586917000	USD
CY2012	us-gaap	Net Income Loss NetIncomeLoss	216717000	USD
CY2012	us-gaap	Inventory Write Down InventoryWriteDown	1700000	USD
CY2013Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7940401000	USD
CY2012Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7495675000	USD
CY2012Q3	us-gaap	Liabilities Current LiabilitiesCurrent	1275954000	USD
CY2013Q3	us-gaap	Liabilities Current LiabilitiesCurrent	978486000	USD
CY2013Q3	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	7676000	USD
CY2012Q3	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	94846000	USD
CY2013Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	3200000	USD
CY2010Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	6700000	USD
CY2013Q3	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	1000000000	USD
CY2012Q3	us-gaap	Long Term Debt Current LongTermDebtCurrent	131000	USD
CY2013Q3	us-gaap	Long Term Debt Current LongTermDebtCurrent	0	USD
CY2013Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1710000000	USD
CY2013Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	USD
CY2013Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	USD
CY2013Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	250000000	USD
CY2013Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	USD
CY2013Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	500000000	USD
CY2012Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1956305000	USD
CY2013Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2455671000	USD
CY2013Q3	us-gaap	Marketable Securities MarketableSecurities	72682000	USD
CY2012Q3	us-gaap	Marketable Securities MarketableSecurities	64398000	USD
CY2013	us-gaap	Maximum Length Of Time Hedged In Cash Flow Hedge1 MaximumLengthOfTimeHedgedInCashFlowHedge1	P0Y55M0D
CY2013	us-gaap	Nature Of Operations NatureOfOperations	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-top:12px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Nature of Business</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Corporation (“Atmos Energy” or the “Company”) and our subsidiaries are engaged primarily in the regulated natural gas distribution and transmission and storage businesses as well as certain other nonregulated businesses. Through our natural gas distribution business, we deliver natural gas through sales and transportation arrangements to over </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">three million</font><font style="font-family:inherit;font-size:10pt;"> residential, commercial, public-authority and industrial customers through our </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">six</font><font style="font-family:inherit;font-size:10pt;"> regulated natural gas distribution divisions in the service areas described below:</font></div><div style="line-height:120%;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3" rowspan="1"></td></tr><tr><td width="48%" rowspan="1" colspan="1"></td><td width="4%" rowspan="1" colspan="1"></td><td width="48%" rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Service Area</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Colorado-Kansas Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Colorado, Kansas</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Kentucky/Mid-States Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Kentucky, Tennessee, Virginia</font><font style="font-family:inherit;font-size:10pt;"><sup style="vertical-align:top;line-height:120%;font-size:7pt">(1)</sup></font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Louisiana Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Louisiana</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Mid-Tex Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Texas, including the Dallas/Fort Worth metropolitan area</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Mississippi Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Mississippi</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy West Texas Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">West Texas</font></div></td></tr></table></div><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"> </font></div><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:33px;" rowspan="1" colspan="1"></td><td rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:top" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;padding-left:9px;"><font style="font-family:inherit;font-size:10pt;"><sup style="vertical-align:top;line-height:120%;font-size:7pt">(1)</sup> </font></div></td><td style="vertical-align:top;" rowspan="1" colspan="1"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Denotes location where we have more limited service areas.</font></div></td></tr></table><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In addition, we transport natural gas for others through our distribution system. Our natural gas distribution business is subject to federal and state regulation and/or regulation by local authorities in each of the states in which our natural gas 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.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Over the last two fiscal years, we have sold our natural gas distribution operations in four states to streamline our regulated operations. On April 1, 2013, we completed the divestiture of our natural gas distribution operations in Georgia, representing approximately </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">64,000</font><font style="font-family:inherit;font-size:10pt;"> customers, and in August 2012, we completed the sale of our natural gas distribution operations in Missouri, Illinois and Iowa, representing approximately </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">84,000</font><font style="font-family:inherit;font-size:10pt;"> customers.</font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our regulated transmission and storage business consists of the regulated operations of our Atmos Pipeline–Texas Division, a division of the Company. This division transports natural gas to our Mid-Tex Division, transports natural gas for third parties and manages five underground storage reservoirs in Texas. We also provide ancillary services customary to the pipeline industry including parking arrangements, lending and sales of inventory on hand. </font></div><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our nonregulated businesses operate primarily in the Midwest and Southeast through various wholly-owned subsidiaries of Atmos Energy Holdings, Inc., (AEH). AEH is a wholly-owned subsidiary of the Company and based in Houston, Texas. Through AEH, we provide natural gas management and transportation services to municipalities, natural gas distribution companies, including certain divisions of Atmos Energy and third parties.</font></div></div>
CY2013	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	85747000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	44009000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-44837000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-627386000	USD
CY2013Q3	us-gaap	Net Income Loss NetIncomeLoss	7536000	USD
CY2013Q2	us-gaap	Net Income Loss NetIncomeLoss	38768000	USD
CY2012Q4	us-gaap	Net Income Loss NetIncomeLoss	80465000	USD
CY2013Q1	us-gaap	Net Income Loss NetIncomeLoss	116425000	USD
CY2011Q4	us-gaap	Net Income Loss NetIncomeLoss	68507000	USD
CY2012Q1	us-gaap	Net Income Loss NetIncomeLoss	109111000	USD
CY2012Q3	us-gaap	Net Income Loss NetIncomeLoss	7967000	USD
CY2012Q2	us-gaap	Net Income Loss NetIncomeLoss	31132000	USD
CY2012	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	191403000	USD
CY2011	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	187608000	USD
CY2013	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	229923000	USD
CY2012	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	191407000	USD
CY2013	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	229928000	USD
CY2011	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	187612000	USD
CY2013	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	segment
CY2013Q3	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	8	state
CY2013	us-gaap	Operating Expenses OperatingExpenses	910171000	USD
CY2012	us-gaap	Operating Expenses OperatingExpenses	877499000	USD
CY2011	us-gaap	Operating Expenses OperatingExpenses	874834000	USD
CY2012	us-gaap	Operating Income Loss OperatingIncomeLoss	446240000	USD
CY2013	us-gaap	Operating Income Loss OperatingIncomeLoss	501879000	USD
CY2011	us-gaap	Operating Income Loss OperatingIncomeLoss	425986000	USD
CY2013Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	86396000	USD
CY2013Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	210178000	USD
CY2012Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	154922000	USD
CY2013Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	50383000	USD
CY2012Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	22791000	USD
CY2012Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	202432000	USD
CY2012Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	81546000	USD
CY2011Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	139471000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	166802000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	16722000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	15057000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	15074000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	14692000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	15584000	USD
CY2013Q3	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	89673000	USD
CY2012Q3	us-gaap	Other Assets Current OtherAssetsCurrent	272782000	USD
CY2013Q3	us-gaap	Other Assets Current OtherAssetsCurrent	70334000	USD
CY2013Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	6765000	USD
CY2012Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	10777000	USD
CY2012Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	14929000	USD
CY2013Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	14474000	USD
CY2013Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	484996000	USD
CY2012Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	451262000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	3103000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-213000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-1647000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	79068000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-2250000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	86698000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-25088000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	853000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	86485000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	86485000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	853000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-25088000	USD
CY2012	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	5029000	USD
CY2013	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	2889000	USD
CY2011	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	3355000	USD
CY2012	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	1881000	USD
CY2011	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-953000	USD
CY2013	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-186000	USD
CY2012	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	484000	USD
CY2011	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	228000	USD
CY2013	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	679000	USD
CY2013	us-gaap	Other Information Pertaining To Income Taxes OtherInformationPertainingToIncomeTaxes	results for fiscal 2012 were favorably impacted by a state tax benefit of $13.6 million. Due to the completion of the sale of our Missouri, Iowa and Illinois service areas in the fiscal fourth quarter, the Company updated its analysis of the tax rate at which deferred taxes would reverse in the future to reflect the sale of these service areas. The updated analysis supported a reduction in the deferred tax rate which when applied to the balance of taxable income deferred to future periods resulted in a reduction of the Company’s overall deferred tax liability.
CY2012Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	489665000	USD
CY2013Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	368891000	USD
CY2013Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	43696000	USD
CY2012Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	50730000	USD
CY2012	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	493000	USD
CY2011	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	961000	USD
CY2013	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	2887000	USD
CY2012	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-14644000	USD
CY2013	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-197000	USD
CY2011	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	21184000	USD
CY2012	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	453613000	USD
CY2011	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	442965000	USD
CY2013	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	488020000	USD
CY2011	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	-20079000	USD
CY2012	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	0	USD
CY2013	us-gaap	Payments For Proceeds From Hedge Financing Activities PaymentsForProceedsFromHedgeFinancingActivities	66626000	USD
CY2013	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4904000	USD
CY2011	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4421000	USD
CY2012	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4625000	USD
CY2011	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	124011000	USD
CY2012	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	125796000	USD
CY2013	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	128115000	USD
CY2011	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	622965000	USD
CY2012	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	732858000	USD
CY2013	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	845033000	USD
CY2012Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	39625000	USD
CY2013Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	22940000	USD
CY2013Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	358787000	USD
CY2012Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	457196000	USD
CY2012Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	17114000	USD
CY2013Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	21666000	USD
CY2013	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;">Basis of comparison</font><font style="font-family:inherit;font-size:10pt;"> — Certain prior-year amounts have been reclassified to conform with the current year presentation.</font></div></div>
CY2011	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	7796000	USD
CY2013	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	46000	USD
CY2012	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1606000	USD
CY2011	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	394466000	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2013	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	493793000	USD
CY2011	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	27803000	USD
CY2013	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	USD
CY2012	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	USD
CY2012	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	354141000	USD
CY2013	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-208070000	USD
CY2011	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	83306000	USD
CY2013	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	153023000	USD
CY2011	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2012	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	128223000	USD
CY2012Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	7134470000	USD
CY2013Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	7722019000	USD
CY2012Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5475604000	USD
CY2013Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6030655000	USD
CY2011	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	4286435000	USD
CY2013	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3886257000	USD
CY2012Q3	us-gaap	Regulatory Assets RegulatoryAssets	392263000	USD
CY2012Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	358495000	USD
CY2013Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	273287000	USD
CY2012Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	488397000	USD
CY2013Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	453581000	USD
CY2012Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	5638000	USD
CY2013	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0333
CY2012	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.036
CY2011	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.036
CY2013	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-7417000	USD
CY2012Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	23072000	USD
CY2013Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	16481000	USD
CY2012Q4	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	1034155000	USD
CY2013Q2	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	857935000	USD
CY2013Q3	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	685171000	USD
CY2013Q1	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	1308996000	USD
CY2012Q1	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	1225509000	USD
CY2011Q4	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	1083994000	USD
CY2012Q3	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	552566000	USD
CY2012Q2	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	576414000	USD
CY2013Q3	us-gaap	Regulatory Assets RegulatoryAssets	286748000	USD
CY2012	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3438483000	USD
CY2013Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	1123000	USD
CY2013	us-gaap	Regulatory Noncurrent Asset Amortization Period RegulatoryNoncurrentAssetAmortizationPeriod	20 years
CY2013	us-gaap	Remaining Recovery Period Of Regulatory Assets For Which No Return On Investment During Recovery Period Is Provided1 RemainingRecoveryPeriodOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided1	P15Y
CY2011	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	360131000	USD
CY2012	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	257034000	USD
CY2013	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	131000	USD
CY2013Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	775267000	USD
CY2012Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	660932000	USD
CY2013	us-gaap	Share Based Compensation ShareBasedCompensation	17814000	USD
CY2011	us-gaap	Share Based Compensation ShareBasedCompensation	11586000	USD
CY2012	us-gaap	Share Based Compensation ShareBasedCompensation	19222000	USD
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	39963	shares
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	56842	shares
CY2013	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	25718	shares
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	29.83
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	27.56
CY2013	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	33.42
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	491345	shares
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	532711	shares
CY2013	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	473775	shares
CY2011	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	33.10
CY2012	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	33.44
CY2013	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	40.48
CY2013	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	657795	shares
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	494308	shares
CY2013	us-gaap	Use Of Estimates UseOfEstimates	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;">Use of estimates</font><font style="font-family:inherit;font-size:10pt;"> — 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, legal and environmental accruals, insurance accruals, pension and postretirement obligations, deferred income taxes, asset retirement obligations, impairment of long-lived assets, risk management and trading activities, fair value measurements and the valuation of goodwill and other long-lived assets. Actual results could differ from those estimates.</font></div></div>
CY2013	ato	Cash Flow Hedge Gain Loss To Be Recassiflied Total CashFlowHedgeGainLossToBeRecassifliedTotal	-34840000	USD
CY2013	ato	Cash Flow Hedge Gain Loss To Be Reclassifed Year Two CashFlowHedgeGainLossToBeReclassifedYearTwo	-1229000	USD
CY2013	ato	Cash Flow Hedge Gain Loss To Be Reclassified After Year Five CashFlowHedgeGainLossToBeReclassifiedAfterYearFive	-24569000	USD
CY2013	ato	Cash Flow Hedge Gain Loss To Be Reclassified Year Five CashFlowHedgeGainLossToBeReclassifiedYearFive	-967000	USD
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	464321	shares
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	12600000	USD
CY2013	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	21200000	USD
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	13000000	USD
CY2011	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	27.21
CY2012	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	26.32
CY2013	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	32.20
CY2013Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	8700000	shares
CY2013Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	7930	shares
CY2013Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	25.96
CY2013	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Expiration Period SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod	P10Y
CY2013Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	367984000	USD
CY2012Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	570929000	USD
CY2012	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	13600000	USD
CY2011	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	9958000	USD
CY2012	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	17752000	USD
CY2013	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	15934000	USD
CY2013Q3	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	5000000	shares
CY2011Q3	us-gaap	Stock Repurchase Program Period In Force1 StockRepurchaseProgramPeriodInForce1	P5Y0M0D
CY2013	us-gaap	Stock Repurchased And Retired During Period Shares StockRepurchasedAndRetiredDuringPeriodShares	3334048	shares
CY2010Q3	us-gaap	Stock Repurchased And Retired During Period Shares StockRepurchasedAndRetiredDuringPeriodShares	2958580	shares
CY2011Q2	us-gaap	Stock Repurchased And Retired During Period Shares StockRepurchasedAndRetiredDuringPeriodShares	375468	shares
CY2013	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	387991	shares
CY2013	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	12500000	USD
CY2012Q3	us-gaap	Stockholders Equity StockholdersEquity	2359243000	USD
CY2013Q3	us-gaap	Stockholders Equity StockholdersEquity	2580409000	USD
CY2010Q3	us-gaap	Stockholders Equity StockholdersEquity	2178348000	USD
CY2011Q3	us-gaap	Stockholders Equity StockholdersEquity	2255421000	USD
CY2012Q3	us-gaap	Supplies Supplies	5872000	USD
CY2013Q3	us-gaap	Supplies Supplies	5511000	USD
CY2011	us-gaap	Tax Adjustments Settlements And Unusual Provisions TaxAdjustmentsSettlementsAndUnusualProvisions	-5000000	USD
CY2011	us-gaap	Taxes Other TaxesOther	177767000	USD
CY2013	us-gaap	Taxes Other TaxesOther	187072000	USD
CY2012	us-gaap	Taxes Other TaxesOther	181073000	USD
CY2013Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	66960000	USD
CY2012Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	64319000	USD
CY2012	us-gaap	Undistributed Earnings Allocated To Participating Securities UndistributedEarningsAllocatedToParticipatingSecurities	793000	USD
CY2013	us-gaap	Undistributed Earnings Allocated To Participating Securities UndistributedEarningsAllocatedToParticipatingSecurities	775000	USD
CY2011	us-gaap	Undistributed Earnings Allocated To Participating Securities UndistributedEarningsAllocatedToParticipatingSecurities	1980000	USD
CY2011	us-gaap	Unrealized Gain Loss On Price Risk Fair Value Hedging Instruments UnrealizedGainLossOnPriceRiskFairValueHedgingInstruments	-10400000	USD
CY2012	us-gaap	Unrealized Gain Loss On Price Risk Fair Value Hedging Instruments UnrealizedGainLossOnPriceRiskFairValueHedgingInstruments	-8000000	USD
CY2013	us-gaap	Unrealized Gain Loss On Price Risk Fair Value Hedging Instruments UnrealizedGainLossOnPriceRiskFairValueHedgingInstruments	9000000	USD
CY2011	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	90652000	shares
CY2013	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	91711000	shares
CY2012	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	91172000	shares
CY2011	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	90201000	shares
CY2013	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	90533000	shares
CY2012	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	90150000	shares
CY2010Q3	ato	Accelerated Share Repurchases Payment AcceleratedShareRepurchasesPayment	100000000	USD
CY2010Q3	ato	Accelerated Share Repurchases Payment AcceleratedShareRepurchasesPayment	100000000	USD
CY2013Q3	ato	Accelerated Share Repurchases Payment AcceleratedShareRepurchasesPayment	100000000	USD
CY2012Q3	ato	Accrued Gas Payable AccruedGasPayable	81658000	USD
CY2013Q3	ato	Accrued Gas Payable AccruedGasPayable	121202000	USD
CY2012	ato	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units Discontinued Operations AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnitsDiscontinuedOperations	0	USD
CY2011	ato	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units Discontinued Operations AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnitsDiscontinuedOperations	0	USD
CY2013	ato	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units Discontinued Operations AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnitsDiscontinuedOperations	0	USD
CY2013Q3	ato	Annual Maximum Investment For Direct Stock Purchase Plan AnnualMaximumInvestmentForDirectStockPurchasePlan	100000	USD
CY2011	ato	Asset Impairment Charges Fort Necessity AssetImpairmentChargesFortNecessity	19300000	USD
CY2011	ato	Asset Impairment Charges Park City AssetImpairmentChargesParkCity	11000000	USD
CY2012	ato	Asset Impairment Charges Park City AssetImpairmentChargesParkCity	5300000	USD
CY2013Q3	ato	Asset Retirement Costs In Property Plant And Equipment AssetRetirementCostsInPropertyPlantAndEquipment	3300000	USD
CY2012Q3	ato	Asset Retirement Costs In Property Plant And Equipment AssetRetirementCostsInPropertyPlantAndEquipment	5800000	USD
CY2013Q3	ato	Authorized Commercial Paper AuthorizedCommercialPaper	950000000	USD
CY2012Q3	ato	Available For Sale Securities Gross Unrealized Gain Accumulated In Investments AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments	9061000	USD
CY2013Q3	ato	Available For Sale Securities Gross Unrealized Gain Accumulated In Investments AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments	8706000	USD
CY2012Q3	ato	Available For Sale Securities Gross Unrealized Loss Accumulated In Investments AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments	2000	USD
CY2013Q3	ato	Available For Sale Securities Gross Unrealized Loss Accumulated In Investments AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments	47000	USD
CY2012Q3	ato	Available For Sale Securities Supplemental Executive Benefit Plans AvailableForSaleSecuritiesSupplementalExecutiveBenefitPlans	41800000	USD
CY2013Q3	ato	Available For Sale Securities Supplemental Executive Benefit Plans AvailableForSaleSecuritiesSupplementalExecutiveBenefitPlans	44500000	USD
CY2013	ato	Business License Tax Examination Description BusinessLicenseTaxExaminationDescription	Atmos Energy, through its affiliate, AEM, has been involved in a dispute with the Tennessee Department of Revenue (TDOR) regarding sales business tax audits over a period of several years. AEM has challenged the assessment of the business tax. With respect to certain issues, AEM and the TDOR filed competing Partial Motions for Summary Judgment with the Chancery Court. On August 2, 2013, the Chancery Court granted the TDOR's Partial Motion for Summary Judgment and denied AEM's Partial Motion for Summary Judgment. The Company anticipates a decision by the Chancery Court on the remaining issues in fiscal 2014. AEM has been assessed $6.1 million in business taxes and $3.7 million in penalties and interest for the period from December 2002 through March 31, 2012. We have accrued what we believe to be an adequate amount for the anticipated resolution of this matter and we will continue to review and if appropriate adjust this reserve until this matter is resolved. We continue to believe the final outcome will not have a material adverse effect on our financial condition, results of operations or cash flows.
CY2013Q3	ato	Cash Collateral Right To Reclaim Cash CashCollateralRightToReclaimCash	24800000	USD
CY2012Q3	ato	Cash Collateral Right To Reclaim Cash CashCollateralRightToReclaimCash	23700000	USD
CY2011	ato	Cash Flow Hedge Gain Loss Impacton Earnings CashFlowHedgeGainLossImpactonEarnings	-4667000	USD
CY2013	ato	Cash Flow Hedge Gain Loss Impacton Earnings CashFlowHedgeGainLossImpactonEarnings	-14170000	USD
CY2012	ato	Cash Flow Hedge Gain Loss Impacton Earnings CashFlowHedgeGainLossImpactonEarnings	-66056000	USD
CY2011	ato	Cash Flow Hedge Gain Loss Included In Cost Of Sales Net CashFlowHedgeGainLossIncludedInCostOfSalesNet	-30015000	USD
CY2013	ato	Cash Flow Hedge Gain Loss Included In Cost Of Sales Net CashFlowHedgeGainLossIncludedInCostOfSalesNet	-10681000	USD
CY2012	ato	Cash Flow Hedge Gain Loss Included In Cost Of Sales Net CashFlowHedgeGainLossIncludedInCostOfSalesNet	-64047000	USD
CY2011	ato	Cash Flow Hedge Gain Loss Reclassifiedto Purchased Gas Cost Net CashFlowHedgeGainLossReclassifiedtoPurchasedGasCostNet	-28430000	USD
CY2013	ato	Cash Flow Hedge Gain Loss Reclassifiedto Purchased Gas Cost Net CashFlowHedgeGainLossReclassifiedtoPurchasedGasCostNet	-10778000	USD
CY2012	ato	Cash Flow Hedge Gain Loss Reclassifiedto Purchased Gas Cost Net CashFlowHedgeGainLossReclassifiedtoPurchasedGasCostNet	-62678000	USD
CY2013	ato	Cash Flow Hedge Gain Loss To Be Reclassified Year Four CashFlowHedgeGainLossToBeReclassifiedYearFour	-844000	USD
CY2013	ato	Cash Flow Hedge Gain Loss To Be Reclassified Year Three CashFlowHedgeGainLossToBeReclassifiedYearThree	-797000	USD
CY2013Q3	ato	Cash Held In Margin Accounts Classified Current Risk Management Asset CashHeldInMarginAccountsClassifiedCurrentRiskManagementAsset	16200000	USD
CY2012Q3	ato	Cash Held In Margin Accounts Classified Current Risk Management Asset CashHeldInMarginAccountsClassifiedCurrentRiskManagementAsset	17800000	USD
CY2013Q3	ato	Cash Held In Margin Accounts Offset Current Risk Management Liabilities CashHeldInMarginAccountsOffsetCurrentRiskManagementLiabilities	8600000	USD
CY2012Q3	ato	Cash Held In Margin Accounts Offset Current Risk Management Liabilities CashHeldInMarginAccountsOffsetCurrentRiskManagementLiabilities	5900000	USD
CY2013Q3	ato	Commercial Paper Weighted Average Interest Rate CommercialPaperWeightedAverageInterestRate	0.0025
CY2012Q3	ato	Commercial Paper Weighted Average Interest Rate CommercialPaperWeightedAverageInterestRate	0.0048
CY2012Q3	ato	Common Stock Stated Value Per Share CommonStockStatedValuePerShare	0.005
CY2013Q3	ato	Common Stock Stated Value Per Share CommonStockStatedValuePerShare	0.005
CY2013Q3	ato	Contractual Demand Fees Demand Fees Due Fifth Fiscal Year ContractualDemandFeesDemandFeesDueFifthFiscalYear	142000	USD
CY2013Q3	ato	Contractual Demand Fees Demand Fees Due Fourth Fiscal Year ContractualDemandFeesDemandFeesDueFourthFiscalYear	170000	USD
CY2013Q3	ato	Contractual Demand Fees Demand Fees Due Next Fiscal Year ContractualDemandFeesDemandFeesDueNextFiscalYear	12662000	USD
CY2013Q3	ato	Contractual Demand Fees Demand Fees Due Second Fiscal Year ContractualDemandFeesDemandFeesDueSecondFiscalYear	5113000	USD
CY2013Q3	ato	Contractual Demand Fees Demand Fees Due Thereafter ContractualDemandFeesDemandFeesDueThereafter	356000	USD
CY2013Q3	ato	Contractual Demand Fees Demand Fees Due Third Fiscal Year ContractualDemandFeesDemandFeesDueThirdFiscalYear	743000	USD
CY2013Q3	ato	Debt And Equity Securities Authorized For Issuance DebtAndEquitySecuritiesAuthorizedForIssuance	1750000000	USD
CY2013Q3	ato	Debt And Equity Securities Available For Issuance DebtAndEquitySecuritiesAvailableForIssuance	1750000000	USD
CY2013	ato	Debt Covenant Total Debt To Total Capital Ratio DebtCovenantTotalDebtToTotalCapitalRatio	0.7
CY2012Q3	ato	Deferred Tax Assets Customer Advances DeferredTaxAssetsCustomerAdvances	4721000	USD
CY2013Q3	ato	Deferred Tax Assets Customer Advances DeferredTaxAssetsCustomerAdvances	4279000	USD
CY2013Q3	ato	Deferred Tax Assets Deferred Credits DeferredTaxAssetsDeferredCredits	-51000	USD
CY2012Q3	ato	Deferred Tax Assets Deferred Credits DeferredTaxAssetsDeferredCredits	140000	USD
CY2012Q3	ato	Deferred Tax Assets Operating Loss And Credit Carryforwards DeferredTaxAssetsOperatingLossAndCreditCarryforwards	164419000	USD
CY2013Q3	ato	Deferred Tax Assets Operating Loss And Credit Carryforwards DeferredTaxAssetsOperatingLossAndCreditCarryforwards	206996000	USD
CY2012Q3	ato	Deferred Tax Liabilities Pension Liability DeferredTaxLiabilitiesPensionLiability	32812000	USD
CY2013Q3	ato	Deferred Tax Liabilities Pension Liability DeferredTaxLiabilitiesPensionLiability	23480000	USD
CY2012Q3	ato	Defined Contribution Plan Percent Of Equity Securities Issued By Employer And Related Parties Included In Plan Assets DefinedContributionPlanPercentOfEquitySecuritiesIssuedByEmployerAndRelatedPartiesIncludedInPlanAssets	0.049
CY2013Q3	ato	Defined Contribution Plan Percent Of Equity Securities Issued By Employer And Related Parties Included In Plan Assets DefinedContributionPlanPercentOfEquitySecuritiesIssuedByEmployerAndRelatedPartiesIncludedInPlanAssets	0.049
CY2012	ato	Depreciation And Amortization Cash Flow DepreciationAndAmortizationCashFlow	246093000	USD
CY2011	ato	Depreciation And Amortization Cash Flow DepreciationAndAmortizationCashFlow	233155000	USD
CY2013	ato	Depreciation And Amortization Cash Flow DepreciationAndAmortizationCashFlow	236928000	USD
CY2013	ato	Description Of Pending Litigation DescriptionOfPendingLitigation	Since April 2009, Atmos Energy and two subsidiaries of AEH, Atmos Energy Marketing, LLC (AEM) and Atmos Gathering Company, LLC (AGC) (collectively, the Atmos Entities), have been involved in a lawsuit filed in the Circuit Court of Edmonson County, Kentucky related to our Park City Gathering Project. The dispute which gave rise to the litigation involves the amount of royalties due from a third party producer to landowners (who own the mineral rights) for natural gas produced from the landowners’ properties. The third party producer was operating pursuant to leases between the landowners and certain investors/working interest owners. The third party producer filed a petition in bankruptcy, which was subsequently dismissed due to the lack of meaningful assets to reorganize or liquidate. Although certain Atmos Energy companies entered into contracts with the third party producer to gather, treat and ultimately sell natural gas produced from the landowners’ properties, no Atmos Energy company had a contractual relationship with the landowners or the investors/working interest owners. After the lawsuit was filed, the landowners were successful in terminating for non-payment of royalties the leases related to the production of natural gas from their properties. Subsequent to termination, the investors/working interest owners under such leases filed additional claims against us for the termination of the leases. During the trial, the landowners and the investors/working interest owners requested an award of compensatory damages plus punitive damages against us. On December 17, 2010, the jury returned a verdict in favor of the landowners and investor/working interest owners and awarded compensatory damages of $3.8 million and punitive damages of $27.5 million payable by Atmos Energy and the two AEH subsidiaries. A hearing was held on February 28, 2011 to hear a number of motions, including a motion to dismiss the jury verdict and a motion for a new trial. The motions to dismiss the jury verdict and for a new trial were denied. However, the total punitive damages award was reduced from $27.5 million to $24.7 million. On October 17, 2011, we filed our brief of appellants with the Kentucky Court of Appeals (Court), appealing the verdict of the trial court. The appellees in this case subsequently filed their appellees’ brief with the Court on January 16, 2012, with our reply brief being filed with the Court on March 19, 2012. Oral arguments were held in the case on August 27, 2012. In an opinion handed down on January 25, 2013, the Court of Appeals overturned the $28.5 million jury verdict returned against the Atmos Entities. In a unanimous decision by a three-judge panel, the Court of Appeals reversed the claims asserted by the landowners and investors/working interest owners. The Court of Appeals concluded that all of such claims that the Atmos Entities appealed should have been dismissed by the trial court as a matter of law. The Court of Appeals let stand the jury verdict on one claim that Atmos Energy and our subsidiaries chose not to appeal, which was a trespass claim. The jury had awarded a total of $10,000 in compensatory damages to one landowner on that claim. The Court of Appeals vacated all of the other damages awarded by the jury and remanded the case to the trial court for a new trial, solely on the issue of whether punitive damages should be awarded to that landowner and, if so, in what amount.The investors/working interest owners, on February 25, 2013, and the landowners, on March 19, 2013, each filed with the Supreme Court of Kentucky, separate motions for discretionary review of the opinion of the Court of Appeals. We filed a response to the motion filed by the investors/working owners on March 27, 2013 and to the landowners’ motion on April 17, 2013. The decision of the Court of Appeals will not become final until the appellate process is completed. We had previously accrued what we believed to be an adequate amount for the anticipated resolution of this matter and we will continue to maintain this amount in legal reserves until the appellate process in this case has been completed. We continue to believe that the final outcome will not have a material adverse effect on our financial condition, results of operations or cash flows.In addition, in a related development, on July 12, 2011, the Atmos Entities filed a lawsuit in the United States District Court, Western District of Kentucky, Atmos Energy Corporation et al.vs. Resource Energy Technologies, LLC and Robert Thorpe and John F. Charles, against the third party producer and its affiliates to recover all costs, including attorneys’ fees, incurred by the Atmos Entities, which are associated with the defense and appeal of the case discussed above as well as for all damages awarded to the plaintiffs in such case against the Atmos Entities. The total amount of damages being claimed in the lawsuit is “open-ended” since the appellate process and related costs are ongoing. This lawsuit is based upon the indemnification provisions agreed to by the third party producer in favor of Atmos Gathering that are contained in an agreement entered into between Atmos Gathering and the third party producer in May 2009. The defendants filed a motion to dismiss the case on August 25, 2011, with Atmos Energy filing a brief in response to such motion on September 19, 2011. On March 27, 2012 the court denied the motion to dismiss. Since that time, we have been engaged in discovery activities in this case.
CY2012	ato	Discontinued Operations Gross Profit DiscontinuedOperationsGrossProfit	51801000	USD
CY2013	ato	Discontinued Operations Gross Profit DiscontinuedOperationsGrossProfit	16498000	USD
CY2011	ato	Discontinued Operations Gross Profit DiscontinuedOperationsGrossProfit	57690000	USD
CY2012	ato	Discontinued Operations Miscellaneous Income Expense DiscontinuedOperationsMiscellaneousIncomeExpense	611000	USD
CY2011	ato	Discontinued Operations Miscellaneous Income Expense DiscontinuedOperationsMiscellaneousIncomeExpense	57000	USD
CY2013	ato	Discontinued Operations Miscellaneous Income Expense DiscontinuedOperationsMiscellaneousIncomeExpense	548000	USD
CY2011	ato	Discontinued Operations Operating Revenues DiscontinuedOperationsOperatingRevenues	141227000	USD
CY2013	ato	Discontinued Operations Operating Revenues DiscontinuedOperationsOperatingRevenues	37962000	USD
CY2012	ato	Discontinued Operations Operating Revenues DiscontinuedOperationsOperatingRevenues	114703000	USD
CY2011	ato	Discontinued Operations Purchased Gas Cost DiscontinuedOperationsPurchasedGasCost	83537000	USD
CY2013	ato	Discontinued Operations Purchased Gas Cost DiscontinuedOperationsPurchasedGasCost	21464000	USD
CY2012	ato	Discontinued Operations Purchased Gas Cost DiscontinuedOperationsPurchasedGasCost	62902000	USD
CY2012Q3	ato	Disposal Group Including Discontinued Operation Derivative Assets Current DisposalGroupIncludingDiscontinuedOperationDerivativeAssetsCurrent	100000	USD
CY2012Q3	ato	Disposal Group Including Discontinued Operation Derivative Liabilities Current DisposalGroupIncludingDiscontinuedOperationDerivativeLiabilitiesCurrent	300000	USD
CY2012	ato	Gain Loss On Derivative Instruments Not Designated Hedges Net Pretax GainLossOnDerivativeInstrumentsNotDesignatedHedgesNetPretax	-2500000	USD
CY2013	ato	Gain Loss On Derivative Instruments Not Designated Hedges Net Pretax GainLossOnDerivativeInstrumentsNotDesignatedHedgesNetPretax	3000000	USD
CY2011	ato	Gain Loss On Derivative Instruments Not Designated Hedges Net Pretax GainLossOnDerivativeInstrumentsNotDesignatedHedgesNetPretax	-1400000	USD
CY2013	ato	Gain Loss On Hedge Ineffectiveness GainLossOnHedgeIneffectiveness	18200000	USD
CY2011Q1	ato	Liabilityfor Uncertain Tax Positions Decreasedueto Settlement LiabilityforUncertainTaxPositionsDecreaseduetoSettlement	6700000	USD
CY2012	ato	Fair Value Hedge Timing Ineffectiveness FairValueHedgeTimingIneffectiveness	-23299000	USD
CY2012Q3	ato	Disposal Group Including Discontinued Operation Gas Stored Underground DisposalGroupIncludingDiscontinuedOperationGasStoredUnderground	4688000	USD
CY2012Q3	ato	Disposal Group Including Discontinued Operation Regulatory Cost Of Removal Obligation DisposalGroupIncludingDiscontinuedOperationRegulatoryCostOfRemovalObligation	3257000	USD
CY2013	ato	Extinguishmentof Debt Interest Terms ExtinguishmentofDebtInterestTerms	LIBOR based rate plus a company specific spread,
CY2013	ato	Fair Value Hedge Basis Ineffectiveness FairValueHedgeBasisIneffectiveness	208000	USD
CY2011	ato	Fair Value Hedge Basis Ineffectiveness FairValueHedgeBasisIneffectiveness	-803000	USD
CY2012	ato	Fair Value Hedge Basis Ineffectiveness FairValueHedgeBasisIneffectiveness	-1170000	USD
CY2013	ato	Fair Value Hedge Timing Ineffectiveness FairValueHedgeTimingIneffectiveness	-18311000	USD
CY2011	ato	Fair Value Hedge Timing Ineffectiveness FairValueHedgeTimingIneffectiveness	-25573000	USD
CY2011	ato	Gain Loss On Hedge Ineffectiveness GainLossOnHedgeIneffectiveness	24800000	USD
CY2012	ato	Gain Loss On Hedge Ineffectiveness GainLossOnHedgeIneffectiveness	23100000	USD
CY2011	ato	Gain On Unwinding Of Treasury Lock Reclassified From Accumulated Oci To Miscellaneous Income GainOnUnwindingOfTreasuryLockReclassifiedFromAccumulatedOciToMiscellaneousIncome	27803000	USD
CY2012Q3	ato	Gas Gathering Assets Fair Value Nonrecurring GasGatheringAssetsFairValueNonrecurring	500000	USD
CY2012Q3	ato	Goodwill And Intangible Assets GoodwillAndIntangibleAssets	740847000	USD
CY2013Q3	ato	Goodwill And Intangible Assets GoodwillAndIntangibleAssets	741484000	USD
CY2013	ato	Hedge Percentage Of Actual Heating Season Gas HedgePercentageOfActualHeatingSeasonGas	0.33
CY2013	ato	Hedge Volume Of Actual Heating Season Gas HedgeVolumeOfActualHeatingSeasonGas	22800	MMcf
CY2013Q3	ato	Hedged Portion Of Gas Stored Underground Fair Value Disclosure HedgedPortionOfGasStoredUndergroundFairValueDisclosure	44758000	USD
CY2012Q3	ato	Hedged Portion Of Gas Stored Underground Fair Value Disclosure HedgedPortionOfGasStoredUndergroundFairValueDisclosure	67192000	USD
CY2013	ato	Increase Decrease In Other Noncurrent Operating Assets IncreaseDecreaseInOtherNoncurrentOperatingAssets	-111069000	USD
CY2012	ato	Increase Decrease In Other Noncurrent Operating Assets IncreaseDecreaseInOtherNoncurrentOperatingAssets	50055000	USD
CY2011	ato	Increase Decrease In Other Noncurrent Operating Assets IncreaseDecreaseInOtherNoncurrentOperatingAssets	53519000	USD
CY2013	ato	Increase Decrease In Other Noncurrent Operating Liabilities IncreaseDecreaseInOtherNoncurrentOperatingLiabilities	-96658000	USD
CY2011	ato	Increase Decrease In Other Noncurrent Operating Liabilities IncreaseDecreaseInOtherNoncurrentOperatingLiabilities	71691000	USD
CY2012	ato	Increase Decrease In Other Noncurrent Operating Liabilities IncreaseDecreaseInOtherNoncurrentOperatingLiabilities	21424000	USD
CY2011	ato	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights Discontinued Operations IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRightsDiscontinuedOperations	451000	shares
CY2012	ato	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights Discontinued Operations IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRightsDiscontinuedOperations	1022000	shares
CY2013	ato	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights Discontinued Operations IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRightsDiscontinuedOperations	1178000	shares
CY2013Q3	ato	Intercompany Payables IntercompanyPayables	0	USD
CY2012Q3	ato	Intercompany Payables IntercompanyPayables	0	USD
CY2013Q3	ato	Intercompany Receivables IntercompanyReceivables	0	USD
CY2012Q3	ato	Intercompany Receivables IntercompanyReceivables	0	USD
CY2013Q3	ato	Investment In Subsidaries InvestmentInSubsidaries	0	USD
CY2012Q3	ato	Investment In Subsidaries InvestmentInSubsidaries	0	USD
CY2012	ato	Investment Tax Credits InvestmentTaxCredits	27000	USD
CY2011Q4	ato	Loss Contingency Civil Penalty Paidto Energy Assistance Programs LossContingencyCivilPenaltyPaidtoEnergyAssistancePrograms	5600000	USD
CY2011Q4	ato	Loss Contingency Civil Penalty Paidto United States Treasury LossContingencyCivilPenaltyPaidtoUnitedStatesTreasury	6400000	USD
CY2013Q1	ato	Loss Contingency Compensatory Damages Awarded Value LossContingencyCompensatoryDamagesAwardedValue	10000	USD
CY2013	ato	Maximum Hedge Percentage Of Anticipated Heating Season Gas MaximumHedgePercentageOfAnticipatedHeatingSeasonGas	0.50
CY2013	ato	Investment Tax Credits InvestmentTaxCredits	20000	USD
CY2011	ato	Investment Tax Credits InvestmentTaxCredits	172000	USD
CY2013Q3	ato	Lease And Rental Expense1 LeaseAndRentalExpense1	32400000	USD
CY2012Q3	ato	Lease And Rental Expense1 LeaseAndRentalExpense1	33600000	USD
CY2011Q3	ato	Lease And Rental Expense1 LeaseAndRentalExpense1	35500000	USD
CY2012Q3	ato	Liabilities Of Disposal Group LiabilitiesOfDisposalGroup	11573000	USD
CY2013Q3	ato	Liabilities Of Disposal Group LiabilitiesOfDisposalGroup	0	USD
CY2013Q3	ato	Minimum Continuing Investment For Direct Stock Purchase Plan MinimumContinuingInvestmentForDirectStockPurchasePlan	25	USD
CY2013	ato	Minimum Hedge Percentage Of Anticipated Heating Season Gas MinimumHedgePercentageOfAnticipatedHeatingSeasonGas	0.25
CY2013Q3	ato	Minimum Initial Investment For Direct Stock Purchase Plan MinimumInitialInvestmentForDirectStockPurchasePlan	1250	USD
CY2013	ato	Minimum Length Of Time Hedged In Cash Flow Hedge MinimumLengthOfTimeHedgedInCashFlowHedge	P0Y1M0D
CY2012	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Basic NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersBasic	24420000	USD
CY2013	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Basic NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersBasic	12454000	USD
CY2011	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Basic NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersBasic	17825000	USD
CY2013	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersDiluted	12454000	USD
CY2012	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersDiluted	24420000	USD
CY2011	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersDiluted	17825000	USD
CY2013Q3	ato	Net Open Positions NetOpenPositions	0.1	Bcf
CY2013	ato	Nonregulated Segment Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate NonregulatedSegmentEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.39
CY2013Q3	ato	Number Of Customers Natural Gas Distribution NumberOfCustomersNaturalGasDistribution	3000000	customers
CY2013Q3	ato	Number Of Divisions Natural Gas Distribution NumberOfDivisionsNaturalGasDistribution	6	regulated_gas_distributions_divisions
CY2013Q3	ato	Numberof Credit Facilities NumberofCreditFacilities	4	credit_facility
CY2012	ato	Other Comprehensive Income Loss Commodity Cash Flow Hedges Net Of Tax OtherComprehensiveIncomeLossCommodityCashFlowHedgesNetOfTax	7866000	USD
CY2011	ato	Other Comprehensive Income Loss Commodity Cash Flow Hedges Net Of Tax OtherComprehensiveIncomeLossCommodityCashFlowHedgesNetOfTax	5248000	USD
CY2013	ato	Other Comprehensive Income Loss Commodity Cash Flow Hedges Net Of Tax OtherComprehensiveIncomeLossCommodityCashFlowHedgesNetOfTax	4519000	USD
CY2011	ato	Other Comprehensive Income Reclassification Adjustment And Unrealized Gain Loss On Derivatives Included In Net Income And Arising During Period Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentAndUnrealizedGainLossOnDerivativesIncludedInNetIncomeAndArisingDuringPeriodNetOfTax	-28689000	USD
CY2012	ato	Other Comprehensive Income Reclassification Adjustment And Unrealized Gain Loss On Derivatives Included In Net Income And Arising During Period Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentAndUnrealizedGainLossOnDerivativesIncludedInNetIncomeAndArisingDuringPeriodNetOfTax	-10116000	USD
CY2013	ato	Other Comprehensive Income Reclassification Adjustment And Unrealized Gain Loss On Derivatives Included In Net Income And Arising During Period Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentAndUnrealizedGainLossOnDerivativesIncludedInNetIncomeAndArisingDuringPeriodNetOfTax	82179000	USD
CY2012	ato	Other Comprehensive Income Reclassification Adjustment And Unrealized Gain Loss On Derivatives Included In Net Income And Arising During Period Tax OtherComprehensiveIncomeReclassificationAdjustmentAndUnrealizedGainLossOnDerivativesIncludedInNetIncomeAndArisingDuringPeriodTax	-5388000	USD
CY2011	ato	Other Comprehensive Income Reclassification Adjustment And Unrealized Gain Loss On Derivatives Included In Net Income And Arising During Period Tax OtherComprehensiveIncomeReclassificationAdjustmentAndUnrealizedGainLossOnDerivativesIncludedInNetIncomeAndArisingDuringPeriodTax	-16850000	USD
CY2013	ato	Other Comprehensive Income Reclassification Adjustment And Unrealized Gain Loss On Derivatives Included In Net Income And Arising During Period Tax OtherComprehensiveIncomeReclassificationAdjustmentAndUnrealizedGainLossOnDerivativesIncludedInNetIncomeAndArisingDuringPeriodTax	47236000	USD
CY2013	ato	Other Comprehensive Income Reclassification Adjustment On Forward Commodity Contracts Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnForwardCommodityContractsIncludedInNetIncomeNetOfTax	6576000	USD
CY2012	ato	Other Comprehensive Income Reclassification Adjustment On Forward Commodity Contracts Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnForwardCommodityContractsIncludedInNetIncomeNetOfTax	38232000	USD
CY2012	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	1342000	USD
CY2013	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	2216000	USD
CY2012	ato	Other Comprehensive Income Unrealized Gain Loss On Forward Commodity Contracts Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnForwardCommodityContractsArisingDuringPeriodNetOfTax	-30366000	USD
CY2013	ato	Other Comprehensive Income Unrealized Gain Loss On Forward Commodity Contracts Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnForwardCommodityContractsArisingDuringPeriodNetOfTax	-2057000	USD
CY2013	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	79963000	USD
CY2012	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	-11458000	USD
CY2012Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	14118000	USD
CY2013Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	10954000	USD
CY2013Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	17953000	USD
CY2012Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	12555000	USD
CY2013	ato	Payments To Repurchase Common Stock PaymentsToRepurchaseCommonStock	0	USD
CY2011	ato	Payments To Repurchase Common Stock PaymentsToRepurchaseCommonStock	0	USD
CY2012	ato	Payments To Repurchase Common Stock PaymentsToRepurchaseCommonStock	12535000	USD
CY2012Q3	ato	Property Plant And Equipment Excluding Cip Gross PropertyPlantAndEquipmentExcludingCipGross	6860358000	USD
CY2013Q3	ato	Property Plant And Equipment Excluding Cip Gross PropertyPlantAndEquipmentExcludingCipGross	7446272000	USD
CY2012	ato	Public Utilities Plantand Equipment Amountof Acquisition Adjustmentsand Related Accumulated Depreciation PublicUtilitiesPlantandEquipmentAmountofAcquisitionAdjustmentsandRelatedAccumulatedDepreciation	91500000	USD
CY2013	ato	Public Utilities Plantand Equipment Amountof Acquisition Adjustmentsand Related Accumulated Depreciation PublicUtilitiesPlantandEquipmentAmountofAcquisitionAdjustmentsandRelatedAccumulatedDepreciation	83800000	USD
CY2013	ato	Purchased Gas Cost PurchasedGasCost	2474207000	USD
CY2012	ato	Purchased Gas Cost PurchasedGasCost	2114744000	USD
CY2012Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	78525000	USD
CY2013Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	68225000	USD
CY2013Q3	ato	Regulatory Cost Of Removal Obligation RegulatoryCostOfRemovalObligation	359299000	USD
CY2012Q3	ato	Regulatory Cost Of Removal Obligation RegulatoryCostOfRemovalObligation	381164000	USD
CY2012	ato	Repurchase Of Equity Awards RepurchaseOfEquityAwards	5219000	USD
CY2011	ato	Repurchase Of Equity Awards RepurchaseOfEquityAwards	5299000	USD
CY2013	ato	Repurchase Of Equity Awards RepurchaseOfEquityAwards	5150000	USD
CY2012	ato	Repurchase Of Equity Awards Value RepurchaseOfEquityAwardsValue	5219000	USD
CY2011	ato	Repurchase Of Equity Awards Value RepurchaseOfEquityAwardsValue	5299000	USD
CY2013	ato	Repurchase Of Equity Awards Value RepurchaseOfEquityAwardsValue	5150000	USD
CY2011	ato	Purchased Gas Cost PurchasedGasCost	2985615000	USD
CY2013Q3	ato	Ratio Of Total Debt To Total Capital RatioOfTotalDebtToTotalCapital	0.54
CY2013Q3	ato	Regulated Operations Letters Of Credit Outstanding Amount RegulatedOperationsLettersOfCreditOutstandingAmount	5900000	USD
CY2013	ato	Regulated Segments Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate RegulatedSegmentsEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.37
CY2012Q3	ato	Regulatory Asset Future Recoverable Pension Costs RegulatoryAssetFutureRecoverablePensionCosts	7600000	USD
CY2013Q3	ato	Regulatory Asset Future Recoverable Pension Costs RegulatoryAssetFutureRecoverablePensionCosts	17400000	USD
CY2012Q3	ato	Regulatory Cost Of Removal Liability RegulatoryCostOfRemovalLiability	381164000	USD
CY2013Q3	ato	Regulatory Cost Of Removal Liability RegulatoryCostOfRemovalLiability	359299000	USD
CY2012	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Beginning Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberBeginningBalance	1264142	shares
CY2013	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Ending Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberEndingBalance	1052844	shares
CY2012	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Ending Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberEndingBalance	1262582	shares
CY2011	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Ending Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberEndingBalance	1264142	shares
CY2013	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value Beginning Of Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueBeginningOfPeriod	32.46
CY2011	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value Beginning Of Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueBeginningOfPeriod	27.28
CY2012	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value Beginning Of Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueBeginningOfPeriod	29.56
CY2013	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value End Of Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueEndOfPeriod	36.20
CY2011	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value End Of Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueEndOfPeriod	29.56
CY2012	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value End Of Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueEndOfPeriod	32.46
CY2013Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailable	1403439	shares
CY2013	ato	Schedule Of Divisions And Service Areas ScheduleOfDivisionsAndServiceAreas	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-top:6px;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Through our natural gas distribution business, we deliver natural gas through sales and transportation arrangements to over </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">three million</font><font style="font-family:inherit;font-size:10pt;"> residential, commercial, public-authority and industrial customers through our </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">six</font><font style="font-family:inherit;font-size:10pt;"> regulated natural gas distribution divisions in the service areas described below:</font></div><div style="line-height:120%;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3" rowspan="1"></td></tr><tr><td width="48%" rowspan="1" colspan="1"></td><td width="4%" rowspan="1" colspan="1"></td><td width="48%" rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;">Service Area</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Colorado-Kansas Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Colorado, Kansas</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Kentucky/Mid-States Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Kentucky, Tennessee, Virginia</font><font style="font-family:inherit;font-size:10pt;"><sup style="vertical-align:top;line-height:120%;font-size:7pt">(1)</sup></font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Louisiana Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Louisiana</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Mid-Tex Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Texas, including the Dallas/Fort Worth metropolitan area</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy Mississippi Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Mississippi</font></div></td></tr><tr><td style="vertical-align:top;background-color:;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Atmos Energy West Texas Division</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">  </font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">West Texas</font></div></td></tr></table></div><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"> </font></div><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:33px;" rowspan="1" colspan="1"></td><td rowspan="1" colspan="1"></td></tr><tr><td style="vertical-align:top" rowspan="1" colspan="1"><div style="line-height:120%;font-size:10pt;padding-left:9px;"><font style="font-family:inherit;font-size:10pt;"><sup style="vertical-align:top;line-height:120%;font-size:7pt">(1)</sup> </font></div></td><td style="vertical-align:top;" rowspan="1" colspan="1"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Denotes location where we have more limited service areas.</font></div></td></tr></table></div>
CY2013Q3	ato	Segment Reporting Information Other Current Assets SegmentReportingInformationOtherCurrentAssets	598968000	USD
CY2012Q3	ato	Segment Reporting Information Other Current Assets SegmentReportingInformationOtherCurrentAssets	739016000	USD
CY2013Q3	ato	Segment Reporting Information Other Current Liabilities SegmentReportingInformationOtherCurrentLiabilities	608959000	USD
CY2012Q3	ato	Segment Reporting Information Other Current Liabilities SegmentReportingInformationOtherCurrentLiabilities	619513000	USD
CY2013Q3	ato	Segment Reporting Information Other Noncurrent Assets SegmentReportingInformationOtherNoncurrentAssets	375642000	USD
CY2012Q3	ato	Segment Reporting Information Other Noncurrent Assets SegmentReportingInformationOtherNoncurrentAssets	448979000	USD
CY2013Q3	ato	Segment Reporting Information Other Noncurrent Liabilities SegmentReportingInformationOtherNoncurrentLiabilities	37563000	USD
CY2012Q3	ato	Segment Reporting Information Other Noncurrent Liabilities SegmentReportingInformationOtherNoncurrentLiabilities	41524000	USD
CY2013	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Beginning Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberBeginningBalance	1262582	shares
CY2011	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Beginning Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberBeginningBalance	1293960	shares
CY2011	ato	Share Repurchases Amount ShareRepurchasesAmount	0	USD
CY2012	ato	Share Repurchases Amount ShareRepurchasesAmount	12535000	USD
CY2012	ato	Significant Purchase Commitment Amount Description SignificantPurchaseCommitmentAmountDescription	978800000	USD
CY2011	ato	Significant Purchase Commitment Amount Description SignificantPurchaseCommitmentAmountDescription	1498600000	USD
CY2013	ato	Unrecognized Transition Obligation In Regulatory Assets UnrecognizedTransitionObligationInRegulatoryAssets	628000	USD
CY2013	ato	Significant Purchase Commitment Amount Description SignificantPurchaseCommitmentAmountDescription	1246100000	USD
CY2013Q3	ato	Significant Purchase Commitment Remaining Minimum Amount Committed Next Fiscal Year SignificantPurchaseCommitmentRemainingMinimumAmountCommittedNextFiscalYear	230500000	USD
CY2013	ato	Stock Issued During Period Value Direct Stock Purchase Plan StockIssuedDuringPeriodValueDirectStockPurchasePlan	-50000	USD
CY2011	ato	Stock Issued During Period Value Direct Stock Purchase Plan StockIssuedDuringPeriodValueDirectStockPurchasePlan	-54000	USD
CY2012	ato	Stock Issued During Period Value Direct Stock Purchase Plan StockIssuedDuringPeriodValueDirectStockPurchasePlan	-65000	USD
CY2013	ato	Stock Issued During Period Value Directors Stock For Fee Plan StockIssuedDuringPeriodValueDirectorsStockForFeePlan	80000	USD
CY2012	ato	Stock Issued During Period Value Directors Stock For Fee Plan StockIssuedDuringPeriodValueDirectorsStockForFeePlan	78000	USD
CY2011	ato	Stock Issued During Period Value Directors Stock For Fee Plan StockIssuedDuringPeriodValueDirectorsStockForFeePlan	77000	USD
CY2012	ato	Stock Issued During Period Value Long Term Incentive Plan StockIssuedDuringPeriodValueLongTermIncentivePlan	12037000	USD
CY2011	ato	Stock Issued During Period Value Long Term Incentive Plan StockIssuedDuringPeriodValueLongTermIncentivePlan	13889000	USD
CY2013	ato	Stock Issued During Period Value Long Term Incentive Plan StockIssuedDuringPeriodValueLongTermIncentivePlan	8788000	USD
CY2013Q3	ato	Total Estimated Contractual Demand Fees TotalEstimatedContractualDemandFees	19186000	USD
CY2012	ato	Total Unrecognized In Net Periodic Pension Cost TotalUnrecognizedInNetPeriodicPensionCost	288513000	USD
CY2013	ato	Total Unrecognized In Net Periodic Pension Cost TotalUnrecognizedInNetPeriodicPensionCost	170624000	USD
CY2012	ato	Undistributed Earnings From Discontinued Operations Allocated To Participating Securities UndistributedEarningsFromDiscontinuedOperationsAllocatedToParticipatingSecurities	101000	USD
CY2013	ato	Undistributed Earnings From Discontinued Operations Allocated To Participating Securities UndistributedEarningsFromDiscontinuedOperationsAllocatedToParticipatingSecurities	42000	USD
CY2011	ato	Undistributed Earnings From Discontinued Operations Allocated To Participating Securities UndistributedEarningsFromDiscontinuedOperationsAllocatedToParticipatingSecurities	188000	USD
CY2012	ato	Unrecognized Actuarial Lossin Regulatory Assets UnrecognizedActuarialLossinRegulatoryAssets	294447000	USD
CY2013	ato	Unrecognized Actuarial Lossin Regulatory Assets UnrecognizedActuarialLossinRegulatoryAssets	176048000	USD
CY2013	ato	Unrecognized Prior Service Costin Regulatory Assets UnrecognizedPriorServiceCostinRegulatoryAssets	-6052000	USD
CY2012	ato	Unrecognized Prior Service Costin Regulatory Assets UnrecognizedPriorServiceCostinRegulatoryAssets	-7643000	USD
CY2012	ato	Unrecognized Transition Obligation In Regulatory Assets UnrecognizedTransitionObligationInRegulatoryAssets	1709000	USD
CY2013	ato	Weighted Average Cost Of Actual Heating Season Gas WeightedAverageCostOfActualHeatingSeasonGas	4.03
CY2011	ato	Weighted Average Number Of Diluted Shares Outstanding Discontinued Operations WeightedAverageNumberOfDilutedSharesOutstandingDiscontinuedOperations	90652000	shares
CY2012	ato	Weighted Average Number Of Diluted Shares Outstanding Discontinued Operations WeightedAverageNumberOfDilutedSharesOutstandingDiscontinuedOperations	91172000	shares
CY2013	ato	Weighted Average Number Of Diluted Shares Outstanding Discontinued Operations WeightedAverageNumberOfDilutedSharesOutstandingDiscontinuedOperations	91711000	shares
CY2013	dei	Amendment Flag AmendmentFlag	false
CY2013	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--09-30
CY2013	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2013	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2013
CY2013	dei	Document Period End Date DocumentPeriodEndDate	2013-09-30
CY2013	dei	Document Type DocumentType	10-K
CY2013	dei	Entity Central Index Key EntityCentralIndexKey	0000731802
CY2013Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	90912251	shares
CY2013	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2013	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2013Q1	dei	Entity Public Float EntityPublicFloat	3816801052	USD
CY2013	dei	Entity Registrant Name EntityRegistrantName	Atmos Energy Corporation
CY2013	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2013	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes

Files In Submission

Name	View Source	Status
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0000731802-13-000017-index.html	Edgar Link	pending
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ato09302013ex-106c.htm	Edgar Link	pending
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ato0930201_chart-50306.jpg	Edgar Link	pending
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Financial_Report.xls	Edgar Link	pending
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R10.htm	Edgar Link	pending
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$ATO
Atmos Energy Corp Stock $ato

2013 Form 10-K Financial Statement

#000073180213000017 Filed on November 13, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO Atmos Energy Corp Stock $ato

2013 Form 10-K Financial Statement

#000073180213000017 Filed on November 13, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO
Atmos Energy Corp Stock $ato