$ATO
ATMOS ENERGY CORP Stock $ato

$ato Overview Financials Valuation SEC Filings Company Website

2016 Q3 Form 8-K Financial Statement

#000073180217000015 Filed on April 12, 2017

Income Statement

Concept	2016 Q3	2016 Q2	2016 Q1
Revenue	$433.6M	$456.2M	$890.0M
YoY Change	5.47%	0.16%	-24.13%
Cost Of Revenue	$63.90M	$64.60M	$377.4M
YoY Change	-78.88%	-78.8%	-62.97%
Gross Profit	$369.7M	$391.6M	$512.7M
YoY Change	7.39%	6.38%	1.41%
Gross Profit Margin	85.26%	85.84%	57.6%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$76.40M	$73.50M	$72.00M
YoY Change	8.06%	7.3%	5.88%
% of Gross Profit	20.66%	18.77%	14.04%
Operating Expenses	$285.3M	$270.1M	$267.8M
YoY Change	2.48%	2.3%	-1.01%
Operating Profit	$84.45M	$128.4M	$251.7M
YoY Change	13.59%	15.67%	3.99%
Interest Expense	-$30.00M	$27.68M	$27.56M
YoY Change	-3.54%	-0.99%	0.41%
% of Operating Profit	-35.52%	21.56%	10.95%
Other Income/Expense, Net	-$100.0K	$1.118M	-$329.0K
YoY Change	-94.44%	76.34%	-78.92%
Pretax Income	$54.30M	$101.8M	$223.8M
YoY Change	26.28%	12.79%	1.16%
Income Tax	$19.40M	$35.69M	$80.77M
% Of Pretax Income	35.73%	35.05%	36.09%
Net Earnings	$34.24M	$71.19M	$141.8M
YoY Change	45.61%	26.5%	3.0%
Net Earnings / Revenue	7.9%	15.61%	15.93%
Basic Earnings Per Share	$0.33	$0.69	$1.38
Diluted Earnings Per Share	$0.33	$0.69	$1.38
COMMON SHARES
Basic Shares Outstanding	103.8M shares	102.2M shares	102.1M shares
Diluted Shares Outstanding

Balance Sheet

Concept	2016 Q3	2016 Q2	2016 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments	$120.2M	$66.00M	$48.00M
YoY Change	16.9%	53.49%	-50.0%
Cash & Equivalents	$47.53M	$66.21M	$47.92M
Short-Term Investments	$72.70M
Other Short-Term Assets	$88.09M	$60.50M	$52.45M
YoY Change	76.42%	3.25%	-21.86%
Inventory	$179.0M	$245.0M	$191.0M
Prepaid Expenses	$21.49M
Receivables	$215.9M	$277.4M	$361.6M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$681.7M	$648.9M	$652.9M
YoY Change	8.84%	5.23%	-20.15%
LONG-TERM ASSETS
Property, Plant & Equipment	$8.269B	$8.054B	$7.839B
YoY Change	11.28%	11.67%	11.57%
Goodwill	$727.0M	$742.7M	$742.7M
YoY Change	0.1%	0.09%	0.09%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$305.0M	$282.2M	$308.9M
YoY Change	10.75%	-10.05%	-9.39%
Total Long-Term Assets	$9.329B	$9.078B	$8.891B
YoY Change	10.42%	9.8%	9.64%
TOTAL ASSETS
Total Short-Term Assets	$681.7M	$648.9M	$652.9M
Total Long-Term Assets	$9.329B	$9.078B	$8.891B
Total Assets	$10.01B	$9.727B	$9.544B
YoY Change	10.31%	9.49%	6.92%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$196.0M	$199.0M	$227.0M
YoY Change	-17.99%	-12.33%	-23.31%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$829.8M	$670.5M	$626.9M
YoY Change	81.21%	166.08%	178.65%
Long-Term Debt Due	$250.0M	$250.0M
YoY Change
Total Short-Term Liabilities	$1.788B	$1.530B	$1.227B
YoY Change	54.85%	66.9%	20.51%
LONG-TERM LIABILITIES
Long-Term Debt	$2.189B	$2.206B	$2.456B
YoY Change	-10.2%	-10.17%	0.01%
Other Long-Term Liabilities	$245.4M	$228.8M	$237.5M
YoY Change	52.08%	140.9%	30.56%
Total Long-Term Liabilities	$2.434B	$2.434B	$2.693B
YoY Change	-6.34%	-4.54%	2.12%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.788B	$1.530B	$1.227B
Total Long-Term Liabilities	$2.434B	$2.434B	$2.693B
Total Liabilities	$4.222B	$3.964B	$3.920B
YoY Change	12.49%	14.35%	7.24%
SHAREHOLDERS EQUITY
Retained Earnings	$1.263B	$1.273B	$1.245B
YoY Change	17.66%	16.49%	15.83%
Common Stock	$2.389B	$2.372B	$2.256B
YoY Change	7.06%	7.44%	2.91%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$3.463B	$3.467B	$3.345B
YoY Change
Total Liabilities & Shareholders Equity	$10.01B	$9.727B	$9.544B
YoY Change	10.31%	9.49%	6.92%

Cashflow Statement

Concept	2016 Q3	2016 Q2	2016 Q1
OPERATING ACTIVITIES
Net Income	$34.24M	$71.19M	$141.8M
YoY Change	45.61%	26.5%	3.0%
Depreciation, Depletion And Amortization	$76.40M	$73.50M	$72.00M
YoY Change	8.06%	7.3%	5.88%
Cash From Operating Activities	$165.1M	$176.9M	$382.9M
YoY Change	75.08%	0.06%	-25.42%
INVESTING ACTIVITIES
Capital Expenditures	-$297.3M	-$253.7M	-$245.6M
YoY Change	0.41%	12.31%	36.22%
Acquisitions
YoY Change
Other Investing Activities	$900.0K	$3.800M	$2.400M
YoY Change	-88.89%	1800.0%	-500.0%
Cash From Investing Activities	-$296.3M	-$249.9M	-$243.2M
YoY Change	2.88%	10.77%	34.44%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	112.6M	91.20M	-170.6M
YoY Change	-37.17%	-2705.71%	-52.72%
NET CHANGE
Cash From Operating Activities	165.1M	176.9M	382.9M
Cash From Investing Activities	-296.3M	-249.9M	-243.2M
Cash From Financing Activities	112.6M	91.20M	-170.6M
Net Change In Cash	-18.60M	18.20M	-30.90M
YoY Change	28.28%	-134.8%	9.19%
FREE CASH FLOW
Cash From Operating Activities	$165.1M	$176.9M	$382.9M
Capital Expenditures	-$297.3M	-$253.7M	-$245.6M
Free Cash Flow	$462.4M	$430.6M	$628.5M
YoY Change	18.44%	6.93%	-9.4%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2015Q3	ato	Asset Retirement Costs In Property Plant And Equipment AssetRetirementCostsInPropertyPlantAndEquipment	4800000	USD
CY2016Q3	ato	Asset Retirement Costs In Property Plant And Equipment AssetRetirementCostsInPropertyPlantAndEquipment	8100000	USD
CY2015Q3	ato	Available For Sale Securities Supplemental Executive Benefit Plans AvailableForSaleSecuritiesSupplementalExecutiveBenefitPlans	41700000	USD
CY2016Q3	ato	Available For Sale Securities Supplemental Executive Benefit Plans AvailableForSaleSecuritiesSupplementalExecutiveBenefitPlans	41300000	USD
CY2014	ato	Cash Flow Hedge Gain Loss Impacton Earnings CashFlowHedgeGainLossImpactonEarnings	4333000	USD
CY2015	ato	Cash Flow Hedge Gain Loss Impacton Earnings CashFlowHedgeGainLossImpactonEarnings	-42894000	USD
CY2016	ato	Cash Flow Hedge Gain Loss Impacton Earnings CashFlowHedgeGainLossImpactonEarnings	-53216000	USD
CY2014	ato	Cash Flow Hedge Gain Loss Included In Cost Of Sales Net CashFlowHedgeGainLossIncludedInCostOfSalesNet	8563000	USD
CY2015	ato	Cash Flow Hedge Gain Loss Included In Cost Of Sales Net CashFlowHedgeGainLossIncludedInCostOfSalesNet	-42041000	USD
CY2016	ato	Cash Flow Hedge Gain Loss Included In Cost Of Sales Net CashFlowHedgeGainLossIncludedInCostOfSalesNet	-52670000	USD
CY2014	ato	Cash Flow Hedge Gain Loss Reclassifiedto Purchased Gas Cost Net CashFlowHedgeGainLossReclassifiedtoPurchasedGasCostNet	8365000	USD
CY2015	ato	Cash Flow Hedge Gain Loss Reclassifiedto Purchased Gas Cost Net CashFlowHedgeGainLossReclassifiedtoPurchasedGasCostNet	-41716000	USD
CY2016	ato	Cash Flow Hedge Gain Loss Reclassifiedto Purchased Gas Cost Net CashFlowHedgeGainLossReclassifiedtoPurchasedGasCostNet	-52651000	USD
CY2016	ato	Cash Flow Hedge Gain Loss To Be Recassiflied Total CashFlowHedgeGainLossToBeRecassifliedTotal	-23286000	USD
CY2016	ato	Cash Flow Hedge Gain Loss To Be Reclassifed Year Two CashFlowHedgeGainLossToBeReclassifedYearTwo	-1210000	USD
CY2016	ato	Cash Flow Hedge Gain Loss To Be Reclassified After Year Five CashFlowHedgeGainLossToBeReclassifiedAfterYearFive	-15139000	USD
CY2016	ato	Cash Flow Hedge Gain Loss To Be Reclassified Year Five CashFlowHedgeGainLossToBeReclassifiedYearFive	-696000	USD
CY2016Q3	ato	Annual Maximum Investment For Direct Stock Purchase Plan AnnualMaximumInvestmentForDirectStockPurchasePlan	100000	USD
CY2016Q3	ato	Atm Agent Commission Proceeds Percentage ATMAgentCommissionProceedsPercentage	0.01
CY2016	ato	Atm Equity Distribution Gross Proceeds ATMEquityDistributionGrossProceeds	100000000	USD
CY2016	ato	Atm Equity Distribution Net Proceeds ATMEquityDistributionNetProceeds	98600000	USD
CY2016Q3	ato	Atm Equity Distribution Offering Price Maximum Amount ATMEquityDistributionOfferingPriceMaximumAmount	200000000	USD
CY2016	ato	Atm Equity Distribution Shares Issued ATMEquityDistributionSharesIssued	1360756	shares
CY2015Q3	ato	Accrued Gas Payable AccruedGasPayable	56468000	USD
CY2016Q3	ato	Accrued Gas Payable AccruedGasPayable	47107000	USD
CY2014	ato	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units Discontinued Operations AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnitsDiscontinuedOperations	0	USD
CY2015	ato	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units Discontinued Operations AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnitsDiscontinuedOperations	0	USD
CY2016	ato	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units Discontinued Operations AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnitsDiscontinuedOperations	0	USD
CY2016	ato	Cash Flow Hedge Gain Loss To Be Reclassified Year Four CashFlowHedgeGainLossToBeReclassifiedYearFour	-724000	USD
CY2016	ato	Cash Flow Hedge Gain Loss To Be Reclassified Year Three CashFlowHedgeGainLossToBeReclassifiedYearThree	-1087000	USD
CY2016	ato	Charitable Contribution Carryforwards Expiration Date Maximum CharitableContributionCarryforwardsExpirationDateMaximum	2021-12-31
CY2016	ato	Charitable Contribution Carryforwards Expiration Date Minimum CharitableContributionCarryforwardsExpirationDateMinimum	2017-12-31
CY2015Q3	ato	Commercial Paper Weighted Average Interest Rate CommercialPaperWeightedAverageInterestRate	0.0042
CY2016Q3	ato	Commercial Paper Weighted Average Interest Rate CommercialPaperWeightedAverageInterestRate	0.0081
CY2016Q3	ato	Contractual Demand Fees Demand Fees Due Fifth Fiscal Year ContractualDemandFeesDemandFeesDueFifthFiscalYear	327000	USD
CY2016Q3	ato	Contractual Demand Fees Demand Fees Due Fourth Fiscal Year ContractualDemandFeesDemandFeesDueFourthFiscalYear	400000	USD
CY2016Q3	ato	Contractual Demand Fees Demand Fees Due Next Fiscal Year ContractualDemandFeesDemandFeesDueNextFiscalYear	9065000	USD
CY2016Q3	ato	Contractual Demand Fees Demand Fees Due Second Fiscal Year ContractualDemandFeesDemandFeesDueSecondFiscalYear	2336000	USD
CY2016Q3	ato	Contractual Demand Fees Demand Fees Due Thereafter ContractualDemandFeesDemandFeesDueThereafter	678000	USD
CY2016Q3	ato	Contractual Demand Fees Demand Fees Due Third Fiscal Year ContractualDemandFeesDemandFeesDueThirdFiscalYear	424000	USD
CY2016Q3	ato	Debt And Equity Securities Authorized For Issuance DebtAndEquitySecuritiesAuthorizedForIssuance	2500000000.0	USD
CY2016Q3	ato	Debt And Equity Securities Available For Issuance DebtAndEquitySecuritiesAvailableForIssuance	2400000000	USD
CY2015Q3	ato	Deferred Tax Assets Deferred Credits DeferredTaxAssetsDeferredCredits	-412000	USD
CY2016Q3	ato	Deferred Tax Assets Deferred Credits DeferredTaxAssetsDeferredCredits	-861000	USD
CY2015Q3	ato	Intercompany Payables IntercompanyPayables	0	USD
CY2016Q3	ato	Intercompany Payables IntercompanyPayables	0	USD
CY2015Q3	ato	Intercompany Receivables IntercompanyReceivables	0	USD
CY2015Q3	ato	Deferred Tax Liabilities Pension Liability DeferredTaxLiabilitiesPensionLiability	35247000	USD
CY2016Q3	ato	Deferred Tax Liabilities Pension Liability DeferredTaxLiabilitiesPensionLiability	30652000	USD
CY2016	ato	Expirationof Deferred Tax Assets ExpirationofDeferredTaxAssets	200000	USD
CY2014	ato	Fair Value Hedge Basis Ineffectiveness FairValueHedgeBasisIneffectiveness	919000	USD
CY2015	ato	Fair Value Hedge Basis Ineffectiveness FairValueHedgeBasisIneffectiveness	-811000	USD
CY2016	ato	Fair Value Hedge Basis Ineffectiveness FairValueHedgeBasisIneffectiveness	1390000	USD
CY2014	ato	Fair Value Hedge Timing Ineffectiveness FairValueHedgeTimingIneffectiveness	-2613000	USD
CY2015	ato	Fair Value Hedge Timing Ineffectiveness FairValueHedgeTimingIneffectiveness	268000	USD
CY2016	ato	Fair Value Hedge Timing Ineffectiveness FairValueHedgeTimingIneffectiveness	-22985000	USD
CY2014	ato	Gain Loss On Hedge Ineffectiveness GainLossOnHedgeIneffectiveness	1900000	USD
CY2015	ato	Gain Loss On Hedge Ineffectiveness GainLossOnHedgeIneffectiveness	200000	USD
CY2016	ato	Gain Loss On Hedge Ineffectiveness GainLossOnHedgeIneffectiveness	21600000	USD
CY2016	ato	Hedge Percentage Of Actual Heating Season Gas HedgePercentageOfActualHeatingSeasonGas	0.33
CY2016	ato	Hedge Volume Of Actual Heating Season Gas HedgeVolumeOfActualHeatingSeasonGas	23000	MMcf
CY2015Q3	ato	Hedged Portion Of Gas Stored Underground Fair Value Disclosure HedgedPortionOfGasStoredUndergroundFairValueDisclosure	43901000	USD
CY2016Q3	ato	Hedged Portion Of Gas Stored Underground Fair Value Disclosure HedgedPortionOfGasStoredUndergroundFairValueDisclosure	52578000	USD
CY2014	ato	Incomefromcontinuingoperationsavailabletocommonshareholders Incomefromcontinuingoperationsavailabletocommonshareholders	269668000	USD
CY2015	ato	Incomefromcontinuingoperationsavailabletocommonshareholders Incomefromcontinuingoperationsavailabletocommonshareholders	305016000	USD
CY2016	ato	Incomefromcontinuingoperationsavailabletocommonshareholders Incomefromcontinuingoperationsavailabletocommonshareholders	345004000	USD
CY2016Q3	ato	Intercompany Receivables IntercompanyReceivables	0	USD
CY2015Q3	ato	Investment In Subsidaries InvestmentInSubsidaries	0	USD
CY2016Q3	ato	Investment In Subsidaries InvestmentInSubsidaries	0	USD
CY2014	ato	Investment Tax Credits InvestmentTaxCredits	6000	USD
CY2015	ato	Investment Tax Credits InvestmentTaxCredits	6000	USD
CY2016	ato	Investment Tax Credits InvestmentTaxCredits	5000	USD
CY2016	ato	Maximum Hedge Percentage Of Anticipated Heating Season Gas MaximumHedgePercentageOfAnticipatedHeatingSeasonGas	0.50
CY2016Q3	ato	Minimum Continuing Investment For Direct Stock Purchase Plan MinimumContinuingInvestmentForDirectStockPurchasePlan	25	USD
CY2016	ato	Minimum Hedge Percentage Of Anticipated Heating Season Gas MinimumHedgePercentageOfAnticipatedHeatingSeasonGas	0.25
CY2016Q3	ato	Minimum Initial Investment For Direct Stock Purchase Plan MinimumInitialInvestmentForDirectStockPurchasePlan	1250	USD
CY2016	ato	Minimum Length Of Time Hedged In Cash Flow Hedge MinimumLengthOfTimeHedgedInCashFlowHedge	P1M
CY2014	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Basic NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersBasic	19438000	USD
CY2015	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Basic NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersBasic	9433000	USD
CY2016	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Basic NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersBasic	4554000	USD
CY2014	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersDiluted	19438000	USD
CY2015	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersDiluted	9433000	USD
CY2016	ato	Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted NetIncomeLossFromDiscontinuedOperationsAvailableToCommonStockholdersDiluted	4554000	USD
CY2016Q3	ato	Net Open Positions NetOpenPositions	100	MMcf
CY2015	ato	Nonregulated Segment Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate NonregulatedSegmentEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.39
CY2016	ato	Nonregulated Segment Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate NonregulatedSegmentEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.39
CY2016Q3	ato	Number Of Customers Regulated Distribution NumberOfCustomersRegulatedDistribution	3000000	customers
CY2016Q3	ato	Number Of Divisions Regulated Distribution NumberOfDivisionsRegulatedDistribution	6	regulated_gas_distributions_divisions
CY2014Q4	ato	Operatingrevenuefromdiscontinuedoperationnetofeliminations Operatingrevenuefromdiscontinuedoperationnetofeliminations	371524000	USD
CY2015	ato	Other Comprehensive Income Reclassification Adjustment On Forward Commodity Contracts Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnForwardCommodityContractsIncludedInNetIncomeNetOfTax	25448000	USD
CY2016	ato	Other Comprehensive Income Reclassification Adjustment On Forward Commodity Contracts Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnForwardCommodityContractsIncludedInNetIncomeNetOfTax	32117000	USD
CY2015	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	542000	USD
CY2016	ato	Other Comprehensive Income Reclassification Adjustment On Interest Rate Agreements Included In Net Income Net Of Tax OtherComprehensiveIncomeReclassificationAdjustmentOnInterestRateAgreementsIncludedInNetIncomeNetOfTax	347000	USD
CY2015	ato	Other Comprehensive Income Unrealized Gain Loss On Forward Commodity Contracts Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnForwardCommodityContractsArisingDuringPeriodNetOfTax	-49211000	USD
CY2016	ato	Other Comprehensive Income Unrealized Gain Loss On Forward Commodity Contracts Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnForwardCommodityContractsArisingDuringPeriodNetOfTax	-11662000	USD
CY2015	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	-71003000	USD
CY2016	ato	Other Comprehensive Income Unrealized Gain Loss On Interest Rate Agreements Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnInterestRateAgreementsArisingDuringPeriodNetOfTax	-99029000	USD
CY2015Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	1653000	USD
CY2016Q3	ato	Other Liabilities Current Other OtherLiabilitiesCurrentOther	5633000	USD
CY2015Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	28738000	USD
CY2016Q3	ato	Other Liabilities Noncurrent Other OtherLiabilitiesNoncurrentOther	33920000	USD
CY2014	ato	Paymentsfor Proceedsfrom Hedge Financing Activities Cash Collateral PaymentsforProceedsfromHedgeFinancingActivitiesCashCollateral	0	USD
CY2015	ato	Paymentsfor Proceedsfrom Hedge Financing Activities Cash Collateral PaymentsforProceedsfromHedgeFinancingActivitiesCashCollateral	0	USD
CY2016	ato	Paymentsfor Proceedsfrom Hedge Financing Activities Cash Collateral PaymentsforProceedsfromHedgeFinancingActivitiesCashCollateral	25670000	USD
CY2014	ato	Paymentsfor Proceedsfrom Hedge Financing Activities Settlements PaymentsforProceedsfromHedgeFinancingActivitiesSettlements	0	USD
CY2015	ato	Paymentsfor Proceedsfrom Hedge Financing Activities Settlements PaymentsforProceedsfromHedgeFinancingActivitiesSettlements	-13364000	USD
CY2016	ato	Paymentsfor Proceedsfrom Hedge Financing Activities Settlements PaymentsforProceedsfromHedgeFinancingActivitiesSettlements	0	USD
CY2015Q3	ato	Public Utilities Property Plantand Equipment Plantin Service Excluding Construction Workin Progress PublicUtilitiesPropertyPlantandEquipmentPlantinServiceExcludingConstructionWorkinProgress	8931254000	USD
CY2016Q3	ato	Public Utilities Property Plantand Equipment Plantin Service Excluding Construction Workin Progress PublicUtilitiesPropertyPlantandEquipmentPlantinServiceExcludingConstructionWorkinProgress	9958627000	USD
CY2015Q3	ato	Public Utilities Property Plantand Equipment Storage PublicUtilitiesPropertyPlantandEquipmentStorage	286011000	USD
CY2016Q3	ato	Public Utilities Property Plantand Equipment Storage PublicUtilitiesPropertyPlantandEquipmentStorage	353523000	USD
CY2015	ato	Regulated Segments Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate RegulatedSegmentsEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.37
CY2016	ato	Regulated Segments Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate RegulatedSegmentsEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.37
CY2015Q3	ato	Regulatory Asset Future Recoverable Pension Costs RegulatoryAssetFutureRecoverablePensionCosts	16600000	USD
CY2016Q3	ato	Regulatory Asset Future Recoverable Pension Costs RegulatoryAssetFutureRecoverablePensionCosts	12400000	USD
CY2015Q3	ato	Regulatory Cost Of Removal Liability RegulatoryCostOfRemovalLiability	427553000	USD
CY2016Q3	ato	Regulatory Cost Of Removal Liability RegulatoryCostOfRemovalLiability	424281000	USD
CY2015Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	56123000	USD
CY2016Q3	ato	Regulatory Cost Of Removal Liability Current RegulatoryCostOfRemovalLiabilityCurrent	52610000	USD
CY2015Q3	ato	Regulatory Cost Of Removal Obligation RegulatoryCostOfRemovalObligation	427553000	USD
CY2016Q3	ato	Regulatory Cost Of Removal Obligation RegulatoryCostOfRemovalObligation	424281000	USD
CY2015Q3	ato	Segment Reporting Information Other Current Assets SegmentReportingInformationOtherCurrentAssets	458598000	USD
CY2016Q3	ato	Segment Reporting Information Other Current Assets SegmentReportingInformationOtherCurrentAssets	483035000	USD
CY2015Q3	ato	Segment Reporting Information Other Current Liabilities SegmentReportingInformationOtherCurrentLiabilities	622336000	USD
CY2016Q3	ato	Segment Reporting Information Other Current Liabilities SegmentReportingInformationOtherCurrentLiabilities	635570000	USD
CY2015Q3	ato	Segment Reporting Information Other Noncurrent Assets SegmentReportingInformationOtherNoncurrentAssets	275424000	USD
CY2016Q3	ato	Segment Reporting Information Other Noncurrent Assets SegmentReportingInformationOtherNoncurrentAssets	305019000	USD
CY2015Q3	ato	Segment Reporting Information Other Noncurrent Liabilities SegmentReportingInformationOtherNoncurrentLiabilities	161349000	USD
CY2016Q3	ato	Segment Reporting Information Other Noncurrent Liabilities SegmentReportingInformationOtherNoncurrentLiabilities	245374000	USD
CY2013Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Beginning Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberBeginningBalance	1052844	shares
CY2014Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Beginning Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberBeginningBalance	988637	shares
CY2015Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Beginning Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberBeginningBalance	878104	shares
CY2014Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Ending Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberEndingBalance	988637	shares
CY2015Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Ending Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberEndingBalance	878104	shares
CY2016Q3	ato	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Ending Balance ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberEndingBalance	782431	shares
CY2013Q3	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	36.20
CY2014Q3	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	42.22
CY2015Q3	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	48.24
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CY2016Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.00
CY2016	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.05
CY2014	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	12389000	USD
CY2015	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	6141000	USD
CY2016	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	3731000	USD
CY2015Q3	us-gaap	Disposal Group Including Discontinued Operation Assets Noncurrent DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent	30385000	USD
CY2016Q3	us-gaap	Disposal Group Including Discontinued Operation Assets Noncurrent DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent	28616000	USD
CY2014Q4	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	10078000	USD
CY2015Q1	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	15300000	USD
CY2015Q2	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	13672000	USD
CY2015Q3	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	10189000	USD
CY2015Q4	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	9469000	USD
CY2016Q1	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	5260000	USD
CY2016Q2	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	15815000	USD
CY2016Q3	us-gaap	Disposal Group Including Discontinued Operation Gross Profit Loss DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss	6428000	USD
CY2014Q4	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	2841000	USD
CY2015Q1	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	8210000	USD
CY2015Q2	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	6606000	USD
CY2015Q3	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	1506000	USD
CY2015Q4	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	3476000	USD
CY2016Q1	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	-1640000	USD
CY2016Q2	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	8768000	USD
CY2016Q3	us-gaap	Disposal Group Including Discontinued Operation Operating Income Loss DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss	184000	USD
CY2014	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	146248000	USD
CY2015	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	160018000	USD
CY2016	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	175126000	USD
CY2014	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.96
CY2014Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.96
CY2015Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.35
CY2015Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.55
CY2015Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.23
CY2015	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.09
CY2015Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.00
CY2016Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.38
CY2016Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.69
CY2016Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.33
CY2016	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2014	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.96
CY2014	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.96000
CY2014Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.96
CY2015Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.35
CY2015Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.55
CY2015Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.23
CY2015	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.09
CY2015Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.00
CY2016Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.38
CY2016Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.69
CY2016Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.33
CY2016	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2014	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	10800000	USD
CY2015	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	11500000	USD
CY2016	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	9800000	USD
CY2016Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	11400000	USD
CY2016	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y7M0D
CY2015Q3	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	195336000	USD
CY2016Q3	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	179070000	USD
CY2014	us-gaap	Gain Loss On Cash Flow Hedge Ineffectiveness Net GainLossOnCashFlowHedgeIneffectivenessNet	198000	USD
CY2015	us-gaap	Gain Loss On Cash Flow Hedge Ineffectiveness Net GainLossOnCashFlowHedgeIneffectivenessNet	-325000	USD
CY2015Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.31
CY2015Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.51
CY2015Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.23
CY2015	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	3.00
CY2015Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.99
CY2016Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.39
CY2016Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.64
CY2016	us-gaap	Gain Loss On Cash Flow Hedge Ineffectiveness Net GainLossOnCashFlowHedgeIneffectivenessNet	-19000	USD
CY2014	us-gaap	Gain Loss On Fair Value Hedges Recognized In Earnings GainLossOnFairValueHedgesRecognizedInEarnings	1694000	USD
CY2015	us-gaap	Gain Loss On Fair Value Hedges Recognized In Earnings GainLossOnFairValueHedgesRecognizedInEarnings	543000	USD
CY2016	us-gaap	Gain Loss On Fair Value Hedges Recognized In Earnings GainLossOnFairValueHedgesRecognizedInEarnings	21595000	USD
CY2015Q3	us-gaap	Goodwill Goodwill	726257000	USD
CY2016Q3	us-gaap	Goodwill Goodwill	726962000	USD
CY2016	us-gaap	Goodwill Other Increase Decrease GoodwillOtherIncreaseDecrease	-705000	USD
CY2014	us-gaap	Gross Profit GrossProfit	1521844000	USD
CY2014Q4	us-gaap	Gross Profit GrossProfit	413340000	USD
CY2015Q1	us-gaap	Gross Profit GrossProfit	505571000	USD
CY2015Q2	us-gaap	Gross Profit GrossProfit	368134000	USD
CY2015Q3	us-gaap	Gross Profit GrossProfit	344265000	USD
CY2015	us-gaap	Gross Profit GrossProfit	1631310000	USD
CY2015Q4	us-gaap	Gross Profit GrossProfit	434427000	USD
CY2016Q1	us-gaap	Gross Profit GrossProfit	512684000	USD
CY2016Q2	us-gaap	Gross Profit GrossProfit	391629000	USD
CY2016Q3	us-gaap	Gross Profit GrossProfit	369716000	USD
CY2016	us-gaap	Gross Profit GrossProfit	1708456000	USD
CY2014	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	270331000	USD
CY2014Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	96086000	USD
CY2015Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	133142000	USD
CY2015Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	52487000	USD
CY2015Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	23908000	USD
CY2015	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	305623000	USD
CY2015Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	101546000	USD
CY2016Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	143003000	USD
CY2016Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	66143000	USD
CY2016Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	34850000	USD
CY2016	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	345542000	USD
CY2014	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	444943000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	495172000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	542184000	USD
CY2014	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.76
CY2014Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.94
CY2015Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.31
CY2015Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.51
CY2015Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.23
CY2015	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	3.00
CY2015Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.99
CY2016Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.39
CY2016Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.64
CY2016Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.33
CY2016	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	3.33
CY2014	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.76
CY2014Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.94
CY2016Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.33
CY2016	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	3.33
CY2014	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	19486000	USD
CY2014Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	1509000	USD
CY2015Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	4542000	USD
CY2015Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	3794000	USD
CY2015Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-393000	USD
CY2015	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	9452000	USD
CY2015Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	1315000	USD
CY2016Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1193000	USD
CY2016Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	5050000	USD
CY2016Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-610000	USD
CY2016	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	4562000	USD
CY2014	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	174612000	USD
CY2015	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	189549000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	196642000	USD
CY2015Q3	us-gaap	Income Tax Receivable IncomeTaxReceivable	4479000	USD
CY2016Q3	us-gaap	Income Tax Receivable IncomeTaxReceivable	5456000	USD
CY2014	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	6969000	USD
CY2015	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	4998000	USD
CY2016	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1324000	USD
CY2014	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	2307000	USD
CY2015	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	2413000	USD
CY2016	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	2570000	USD
CY2014	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	155730000	USD
CY2015	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	173310000	USD
CY2016	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	189764000	USD
CY2014	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	3654000	USD
CY2015	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1365000	USD
CY2016	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-3009000	USD
CY2014	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	10566000	USD
CY2015	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	12289000	USD
CY2016	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	11133000	USD
CY2014	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-610000	USD
CY2015	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1802000	USD
CY2016	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	7794000	USD
CY2014	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	60465000	USD
CY2015	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-59112000	USD
CY2016	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-5195000	USD
CY2014	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	41408000	USD
CY2015	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-48240000	USD
CY2016	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	4847000	USD
CY2014	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	31996000	USD
CY2015	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-33234000	USD
CY2016	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-20577000	USD
CY2014	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	24411000	USD
CY2016Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	USD
CY2015Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2437515000	USD
CY2016Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2188779000	USD
CY2015	us-gaap	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights	0	shares
CY2016	us-gaap	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights	0	shares
CY2014	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	1500000	USD
CY2015	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2300000	USD
CY2016	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2800000	USD
CY2015	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	11951000	USD
CY2016	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	18739000	USD
CY2014	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	2413000	USD
CY2015	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	896000	USD
CY2016	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-44482000	USD
CY2014	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-28875000	USD
CY2015	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-51614000	USD
CY2016	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	24860000	USD
CY2014	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-19552000	USD
CY2015	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-56025000	USD
CY2016	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	14334000	USD
CY2014	us-gaap	Incremental Common Shares Attributable To Participating Nonvested Shares With Non Forfeitable Dividend Rights IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights	2000	shares
CY2014	us-gaap	Interest Expense InterestExpense	129276000	USD
CY2015	us-gaap	Interest Expense InterestExpense	116241000	USD
CY2016	us-gaap	Interest Expense InterestExpense	114812000	USD
CY2014	us-gaap	Interest Paid InterestPaid	156606000	USD
CY2015	us-gaap	Interest Paid InterestPaid	151334000	USD
CY2016	us-gaap	Interest Paid InterestPaid	154748000	USD
CY2015Q3	us-gaap	Interest Payable Current InterestPayableCurrent	34914000	USD
CY2016Q3	us-gaap	Interest Payable Current InterestPayableCurrent	34863000	USD
CY2014	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-4230000	USD
CY2015	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-853000	USD
CY2016	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-546000	USD
CY2015Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	9075072000	USD
CY2016Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	10010889000	USD
CY2015Q3	us-gaap	Liabilities Current LiabilitiesCurrent	1154823000	USD
CY2016Q3	us-gaap	Liabilities Current LiabilitiesCurrent	1788281000	USD
CY2015Q3	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	74560000	USD
CY2016Q3	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	72900000	USD
CY2015Q3	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Noncurrent LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNoncurrent	347000	USD
CY2016Q3	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Noncurrent LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNoncurrent	316000	USD
CY2016Q3	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	1300000000	USD
CY2015Q3	us-gaap	Long Term Debt Current LongTermDebtCurrent	0	USD
CY2016Q3	us-gaap	Long Term Debt Current LongTermDebtCurrent	250000000	USD
CY2016Q3	us-gaap	Long Term Debt Current LongTermDebtCurrent	250000000	USD
CY2016Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1760000000	USD
CY2016Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	250000000	USD
CY2016Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	USD
CY2016Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	USD
CY2016Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	450000000	USD
CY2014	us-gaap	Net Income Loss NetIncomeLoss	289817000	USD
CY2014Q4	us-gaap	Net Income Loss NetIncomeLoss	97595000	USD
CY2015Q1	us-gaap	Net Income Loss NetIncomeLoss	137684000	USD
CY2015Q2	us-gaap	Net Income Loss NetIncomeLoss	56281000	USD
CY2015Q3	us-gaap	Net Income Loss NetIncomeLoss	23515000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	315075000	USD
CY2015Q3	us-gaap	Marketable Securities MarketableSecurities	74200000	USD
CY2016Q3	us-gaap	Marketable Securities MarketableSecurities	72701000	USD
CY2016	us-gaap	Maximum Length Of Time Hedged In Cash Flow Hedge1 MaximumLengthOfTimeHedgedInCashFlowHedge1	P0Y63M0D
CY2014	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	68225000	USD
CY2015	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	131083000	USD
CY2016	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	303623000	USD
CY2014	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-824979000	USD
CY2015	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-956602000	USD
CY2016	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1079732000	USD
CY2014	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	732813000	USD
CY2015	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	811914000	USD
CY2016	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	794990000	USD
CY2015Q4	us-gaap	Net Income Loss NetIncomeLoss	102861000	USD
CY2016Q1	us-gaap	Net Income Loss NetIncomeLoss	141810000	USD
CY2016Q2	us-gaap	Net Income Loss NetIncomeLoss	71193000	USD
CY2016Q3	us-gaap	Net Income Loss NetIncomeLoss	34240000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	350104000	USD
CY2014	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	269668000	USD
CY2015	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	305016000	USD
CY2016	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	345004000	USD
CY2016	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	segment
CY2016Q3	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	8	state
CY2014	us-gaap	Operating Expenses OperatingExpenses	944622000	USD
CY2015	us-gaap	Operating Expenses OperatingExpenses	1019078000	USD
CY2016	us-gaap	Operating Expenses OperatingExpenses	1051226000	USD
CY2014	us-gaap	Operating Income Loss OperatingIncomeLoss	577222000	USD
CY2014Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	184884000	USD
CY2015Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	242000000	USD
CY2015Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	111001000	USD
CY2015Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	74347000	USD
CY2015	us-gaap	Operating Income Loss OperatingIncomeLoss	612232000	USD
CY2015Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	192729000	USD
CY2016Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	251656000	USD
CY2016Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	128396000	USD
CY2016Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	84449000	USD
CY2016	us-gaap	Operating Income Loss OperatingIncomeLoss	657230000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	125875000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	17073000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	14335000	USD
CY2016Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	15606000	USD
CY2015Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	275424000	USD
CY2016Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	305019000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	2214000	USD
CY2015	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	160018000	USD
CY2016	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	175126000	USD
CY2014	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	32734000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	14479000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	15450000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	16824000	USD
CY2016Q3	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	47714000	USD
CY2014	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	31700000	USD
CY2015	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	32500000	USD
CY2016	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	32600000	USD
CY2015Q3	us-gaap	Other Assets Current OtherAssetsCurrent	49929000	USD
CY2016Q3	us-gaap	Other Assets Current OtherAssetsCurrent	88085000	USD
CY2015Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	1116000	USD
CY2016Q3	us-gaap	Other Assets Miscellaneous Current OtherAssetsMiscellaneousCurrent	7102000	USD
CY2015Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	18283000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-2713000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-465000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-94224000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-78227000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-51271000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-96937000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-78692000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-51271000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-96937000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-78692000	USD
CY2014	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	1199000	USD
CY2015	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-442000	USD
CY2016	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-476000	USD
CY2015Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	447690000	USD
CY2016Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	439085000	USD
CY2015Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	161349000	USD
CY2016Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	245374000	USD
CY2014	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-541000	USD
CY2015	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-359000	USD
CY2016	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-1019000	USD
CY2014	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-3003000	USD
CY2015	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-819000	USD
CY2016	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-234000	USD
CY2014	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	482476000	USD
CY2015	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	516406000	USD
CY2016	us-gaap	Other Selling General And Administrative Expense OtherSellingGeneralAndAdministrativeExpense	538592000	USD
CY2014	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2109000	USD
CY2015	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5422000	USD
CY2016	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-6460000	USD
CY2014	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	8717000	USD
CY2015	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	7985000	USD
CY2016	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	0	USD
CY2014	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	146248000	USD
CY2016Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	297743000	USD
CY2015Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	21654000	USD
CY2016Q3	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	21489000	USD
CY2014Q1	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	390205000	USD
CY2014	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	390205000	USD
CY2015	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2016	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	98574000	USD
CY2014	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2015	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	499060000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	6598990000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	131000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	66000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	7416700000	USD
CY2015	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	29527000	USD
CY2016	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	32551000	USD
CY2014	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	824441000	USD
CY2015	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	963621000	USD
CY2016	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1086950000	USD
CY2015Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	21857000	USD
CY2016Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	36606000	USD
CY2015Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	287373000	USD
CY2016	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2014	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	4274000	USD
CY2015	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	30952000	USD
CY2016	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	34278000	USD
CY2014	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	5215000	USD
CY2015	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	6235000	USD
CY2016	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	6290000	USD
CY2014	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	USD
CY2015	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-5522000	USD
CY2016	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-317000	USD
CY2014	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-171289000	USD
CY2015	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	261232000	USD
CY2016	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	371884000	USD
CY2014	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	24872000	USD
CY2015	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	24889000	USD
CY2016	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	27019000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1794975000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1873900000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Amount Of Acquisition Adjustments1 PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1	-68100000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Amount Of Acquisition Adjustments1 PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1	-59800000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Common PublicUtilitiesPropertyPlantAndEquipmentCommon	740863000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Common PublicUtilitiesPropertyPlantAndEquipmentCommon	732606000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	280421000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	183879000	USD
CY2014	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.033
CY2015	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.033
CY2016	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.032
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	6019001000	USD
CY2016Q3	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	433643000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	8268606000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	41131000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	40515000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	9211675000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	10142506000	USD
CY2015Q3	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	1844117000	USD
CY2016Q3	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	2232927000	USD
CY2015Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	28100000	USD
CY2016Q3	us-gaap	Refundable Gas Costs RefundableGasCosts	20180000	USD
CY2014	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3243904000	USD
CY2014Q4	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	887241000	USD
CY2015Q1	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	1173096000	USD
CY2015Q2	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	455505000	USD
CY2015Q3	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	411143000	USD
CY2015	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	2926985000	USD
CY2015Q4	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	674753000	USD
CY2016Q1	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	890040000	USD
CY2016Q2	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	456212000	USD
CY2016	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	2454648000	USD
CY2015Q3	us-gaap	Regulatory Assets RegulatoryAssets	192339000	USD
CY2016Q3	us-gaap	Regulatory Assets RegulatoryAssets	263623000	USD
CY2015Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	182573000	USD
CY2016Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	214890000	USD
CY2015Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	524532000	USD
CY2016Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	514725000	USD
CY2015Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	3693000	USD
CY2016Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	4152000	USD
CY2016	us-gaap	Remaining Recovery Period Of Regulatory Assets For Which No Return On Investment During Recovery Period Is Provided1 RemainingRecoveryPeriodOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided1	P15Y
CY2014	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2015	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	500000000	USD
CY2016	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2015Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1073029000	USD
CY2016Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1262534000	USD
CY2014	us-gaap	Share Based Compensation ShareBasedCompensation	14721000	USD
CY2015	us-gaap	Share Based Compensation ShareBasedCompensation	15980000	USD
CY2016	us-gaap	Share Based Compensation ShareBasedCompensation	14760000	USD
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	4113	shares
CY2015	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	3388	shares
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	4860	shares
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	39.00
CY2015	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	48.55
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	53.52
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	464438	shares
CY2015	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	444543	shares
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	357323	shares
CY2014	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	45.05
CY2015	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	50.50
CY2016	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	65.98
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	524532	shares
CY2015	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	551688	shares
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	448136	shares
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	17100000	USD
CY2015	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	21700000	USD
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	20600000	USD
CY2014	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	32.67
CY2015	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	39.28
CY2016	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	45.88
CY2016Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Additional Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized	2500000.0	shares
CY2015Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	8700000.0	shares
CY2016Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	11200000	shares
CY2016Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	11200000.0	shares
CY2014Q1	us-gaap	Share Price SharePrice	44.00
CY2015Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	457927000	USD
CY2016Q3	us-gaap	Short Term Borrowings ShortTermBorrowings	829811000	USD
CY2014Q1	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	9200000	shares
CY2015	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	20326000	USD
CY2016	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	25049000	USD
CY2014	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	4067000	USD
CY2015	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	10626000	USD
CY2016	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	9229000	USD
CY2014	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	390205000	USD
CY2016	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	98574000	USD
CY2014	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	4353000	USD
CY2015	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2266000	USD
CY2016	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	3178000	USD
CY2014	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	23536000	USD
CY2015	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	25212000	USD
CY2016	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	21419000	USD
CY2014	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	8717000	USD
CY2015	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	7985000	USD
CY2013Q3	us-gaap	Stockholders Equity StockholdersEquity	2580409000	USD
CY2014Q3	us-gaap	Stockholders Equity StockholdersEquity	3086232000	USD
CY2015Q3	us-gaap	Stockholders Equity StockholdersEquity	3194797000	USD
CY2016Q3	us-gaap	Stockholders Equity StockholdersEquity	3463059000	USD
CY2015Q3	us-gaap	Supplies Supplies	12587000	USD
CY2016Q3	us-gaap	Supplies Supplies	5825000	USD
CY2014	us-gaap	Taxes Other TaxesOther	210474000	USD
CY2015	us-gaap	Taxes Other TaxesOther	230264000	USD
CY2016	us-gaap	Taxes Other TaxesOther	221843000	USD
CY2015Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	92912000	USD
CY2016Q3	us-gaap	Taxes Payable Current TaxesPayableCurrent	104145000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	3431000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	3519000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1009000	USD
CY2015Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	11095000	USD
CY2016Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	13194000	USD
CY2014	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	97608000	shares
CY2015	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	101892000	shares
CY2014	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	663000	USD
CY2015	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	607000	USD
CY2016	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	538000	USD
CY2014Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	12629000	USD
CY2015Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17069000	USD
CY2016Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	20298000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	290000	USD
CY2015Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	800000	USD
CY2016Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	3300000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	500000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	2500000	USD
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	103524000	shares
CY2014	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	97606000	shares
CY2015	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	101892000	shares
CY2016	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	103524000	shares
CY2016	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 distribution, pipeline and storage and natural gas marketing segments and interest rate risk. The objectives and strategies for using financial instruments have been tailored to our regulated and natural gas marketing businesses and are discussed in Note </font><font style="font-family:inherit;font-size:10pt;">13</font><font style="font-family:inherit;font-size:10pt;">.</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. We record the cash flow impact of our financial instruments in operating cash flows based upon their balance sheet classification.</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 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 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 natural gas marketing 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 purchased gas cost, which is reflected in income from discontinued operations 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 purchased gas cost 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. For the fiscal years ended </font><font style="font-family:inherit;font-size:10pt;">September 30, 2016</font><font style="font-family:inherit;font-size:10pt;">, </font><font style="font-family:inherit;font-size:10pt;">2015</font><font style="font-family:inherit;font-size:10pt;"> and </font><font style="font-family:inherit;font-size:10pt;">2014</font><font style="font-family:inherit;font-size:10pt;">, we included unrealized gains (losses) on open contracts of </font><font style="font-family:inherit;font-size:10pt;">$1.2 million</font><font style="font-family:inherit;font-size:10pt;">, </font><font style="font-family:inherit;font-size:10pt;">($2.0) million</font><font style="font-family:inherit;font-size:10pt;"> and </font><font style="font-family:inherit;font-size:10pt;">$9.5 million</font><font style="font-family:inherit;font-size:10pt;"> as a component of natural gas marketing purchased gas cost. These amounts are included in income from discontinued operations.</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 natural gas marketing 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 purchased gas cost which is reflected in income from discontinued operations 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 purchased gas cost reflected in income from discontinued operations for the years ended </font><font style="font-family:inherit;font-size:10pt;">September 30, 2016</font><font style="font-family:inherit;font-size:10pt;"> and </font><font style="font-family:inherit;font-size:10pt;">2015</font><font style="font-family:inherit;font-size:10pt;">.</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 natural gas marketing 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, 2016</font><font style="font-family:inherit;font-size:10pt;"> and </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">2015</font><font style="font-family:inherit;font-size:10pt;">, the Company netted $</font><font style="font-family:inherit;font-size:10pt;">24.7 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;">43.5 million</font><font style="font-family:inherit;font-size:10pt;"> of cash held in margin accounts into its current and noncurrent risk management assets and liabilities, which are included in assets and liabilities held for sale.</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, primarily when we plan to issue new long-term debt or to refinance existing long-term debt. We currently manage this risk through the use of forward starting interest rate swaps to fix the Treasury yield component of the interest cost associated with anticipated financings. We designate these financial instruments as cash flow hedges at the time the agreements are executed. Unrealized gains and losses associated with the instruments are recorded as a component of accumulated other comprehensive income (loss). When the instruments settle, the realized gain or loss is recorded as a component of accumulated other comprehensive income (loss) and recognized as a component of interest expense over the life of the related financing arrangement. Hedge ineffectiveness to the extent incurred is reported as a component of interest expense. As of </font><font style="font-family:inherit;font-size:10pt;">September 30, 2016</font><font style="font-family:inherit;font-size:10pt;">, the Company netted </font><font style="font-family:inherit;font-size:10pt;">$25.7 million</font><font style="font-family:inherit;font-size:10pt;"> of cash held in margin accounts into its current and noncurrent risk management liabilities. As of </font><font style="font-family:inherit;font-size:10pt;">September 30, 2015</font><font style="font-family:inherit;font-size:10pt;"> </font><font style="font-family:inherit;font-size:10pt;">no</font><font style="font-family:inherit;font-size:10pt;"> cash was required to be held in margin accounts.</font></div></div>
CY2016	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 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;"> 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 style="width:48%;" rowspan="1" colspan="1"></td><td style="width:4%;" rowspan="1" colspan="1"></td><td style="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>
CY2016	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 pipeline and storage businesses. Through our 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;"> 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 style="width:48%;" rowspan="1" colspan="1"></td><td style="width:4%;" rowspan="1" colspan="1"></td><td style="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-align:left;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 and manage our storage assets located in Kentucky and Tennessee, which are used solely to support our regulated natural gas distribution operations in those states. Our distribution business is subject to federal and state regulation and/or regulation by local authorities in each of the states in which our distribution divisions operate. Our corporate headquarters and shared-services function are located in Dallas, Texas, and our customer support centers are located in Amarillo and Waco, Texas.</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 pipeline and storage business, which is also subject to federal and state regulation, consists of the operations of our Atmos Pipeline–Texas (APT) Division and our Louisiana natural gas transmission business. The APT 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. Our natural gas transmission operations in Louisiana are comprised of a proprietary 21-mile pipeline located in New Orleans, Louisiana that is primarily used to aggregate gas supply for our distribution division in Louisiana under a long-term contract and on a more limited basis, to third parties. </font></div><div style="line-height:120%;padding-top:6px;text-indent:30px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">On October 29, 2016, we entered into a Membership Interest Purchase Agreement (the Agreement) with CenterPoint Energy Services, Inc., a subsidiary of CenterPoint Energy, Inc. (CES) to sell all of the equity interests of AEM. AEM’s historical financial results are reflected in the Company’s consolidated financial statements as discontinued operations, which required retrospective application to financial information for all periods presented. Refer to Note 15, "Discontinued Operations," of the notes to consolidated financial statements for further information. Our discontinued natural gas marketing segment is primarily engaged in a nonregulated natural gas marketing business, conducted by Atmos Energy Marketing (AEM). The natural gas marketing business operates primarily in the Midwest and Southeast and is based in Houston, Texas. This business provides natural gas management and transportation services to municipalities, regulated distribution companies, including certain divisions of Atmos Energy, and third parties.</font></div><div style="line-height:120%;padding-top:6px;text-align:left;text-indent:32px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Additionally, as a result of the announced sale of AEM, we revised the information used by the chief operating decision maker to manage the Company, which led to a change in our reportable segments and required retrospective application to our financial information for all periods presented. Refer to Note 3, “Segment Information,” of the notes to consolidated financial statements for further information.</font></div></div>
CY2016	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;">— As described under Recent Accounting Pronouncements below, we reclassified debt issuance costs from deferred charges and other assets to long-term debt. Additionally, we recorded immaterial corrections to the presentation of certain activities on our Consolidated Statement of Cash Flows for the years ended September 30, 2015 and 2014.</font></div></div>
CY2016	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, contingency accruals, pension and postretirement obligations, deferred income taxes, 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>

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2016 Q3 Form 8-K Financial Statement

#000073180217000015 Filed on April 12, 2017

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$ATO ATMOS ENERGY CORP Stock $ato

2016 Q3 Form 8-K Financial Statement

#000073180217000015 Filed on April 12, 2017

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATO
ATMOS ENERGY CORP Stock $ato