$OGS
ONE Gas, Inc. Stock $ogs

$ogs Overview Financials Valuation SEC Filings Company Website

2017 Q4 Form 10-K Financial Statement

#000158773218000014 Filed on February 22, 2018

Income Statement

Concept	2017 Q4	2017	2016 Q4
Revenue	$462.4M	$1.540B	$440.8M
YoY Change	4.9%	7.88%	13.29%
Cost Of Revenue	$210.0M	$614.5M	$197.4M
YoY Change	6.38%	13.42%	25.17%
Gross Profit	$252.4M	$925.1M	$243.4M
YoY Change	3.7%	4.48%	5.18%
Gross Profit Margin	54.58%	60.09%	55.22%
Selling, General & Admin	$120.0M	$456.5M	$127.5M
YoY Change	-5.88%	0.84%	3.57%
% of Gross Profit	47.54%	49.34%	52.38%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$38.60M	$151.9M	$37.30M
YoY Change	3.49%	5.63%	8.43%
% of Gross Profit	15.29%	16.42%	15.32%
Operating Expenses	$158.6M	$608.4M	$164.8M
YoY Change	-3.76%	1.99%	4.63%
Operating Profit	$93.83M	$316.7M	$78.53M
YoY Change	19.47%	9.61%	6.27%
Interest Expense	-$11.80M	$46.07M	-$11.20M
YoY Change	5.36%	5.32%	1.82%
% of Operating Profit	-12.58%	14.54%	-14.26%
Other Income/Expense, Net	-$3.500M	-$14.53M	-$300.0K
YoY Change	1066.67%	-26.9%	-62.5%
Pretax Income	$78.50M	$256.1M	$67.00M
YoY Change	17.16%	13.67%	7.72%
Income Tax	$29.20M	$93.14M	$24.70M
% Of Pretax Income	37.2%	36.36%	36.87%
Net Earnings	$47.12M	$163.0M	$42.32M
YoY Change	11.35%	16.35%	7.94%
Net Earnings / Revenue	10.19%	10.59%	9.6%
Basic Earnings Per Share	$0.90	$3.10	$0.81
Diluted Earnings Per Share	$0.89	$3.08	$0.80
COMMON SHARES
Basic Shares Outstanding	52.27M shares	52.53M shares	52.25M shares
Diluted Shares Outstanding		52.98M shares

Balance Sheet

Concept	2017 Q4	2017	2016 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$14.40M	$14.40M	$14.70M
YoY Change	-2.04%	-2.04%	512.5%
Cash & Equivalents	$14.41M	$14.40M	$14.66M
Short-Term Investments
Other Short-Term Assets	$17.81M	$106.0M	$20.65M
YoY Change	-13.78%	3.52%	23.02%
Inventory	$169.8M	$169.8M	$159.5M
Prepaid Expenses
Receivables	$298.8M	$298.8M	$290.9M
Other Receivables	$0.00	$0.00	$1.400M
Total Short-Term Assets	$589.0M	$589.0M	$568.9M
YoY Change	3.53%	3.53%	17.83%
LONG-TERM ASSETS
Property, Plant & Equipment	$4.008B	$4.008B	$3.732B
YoY Change	7.4%	7.4%	6.26%
Goodwill	$158.0M		$158.0M
YoY Change	0.0%		0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$47.16M	$452.3M	$43.77M
YoY Change	7.73%	-6.61%	-5.24%
Total Long-Term Assets	$4.618B	$4.618B	$4.374B
YoY Change	5.58%	5.58%	5.35%
TOTAL ASSETS
Total Short-Term Assets	$589.0M	$589.0M	$568.9M
Total Long-Term Assets	$4.618B	$4.618B	$4.374B
Total Assets	$5.207B	$5.207B	$4.943B
YoY Change	5.34%	5.34%	6.65%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$143.7M	$143.7M	$132.0M
YoY Change	8.86%	8.86%	22.8%
Accrued Expenses	$30.06M	$90.20M	$22.93M
YoY Change	31.08%	6.87%	-27.13%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$357.2M	$0.00
YoY Change		146.34%	-100.0%
Long-Term Debt Due	$8.000K		$7.000K
YoY Change	14.29%		0.0%
Total Short-Term Liabilities	$673.3M	$673.3M	$443.9M
YoY Change	51.67%	51.68%	45.92%
LONG-TERM LIABILITIES
Long-Term Debt	$1.193B	$1.193B	$1.192B
YoY Change	0.07%	0.08%	0.07%
Other Long-Term Liabilities	$87.78M	$780.1M	$76.06M
YoY Change	15.41%	105.51%	3.85%
Total Long-Term Liabilities	$1.281B	$1.973B	$1.269B
YoY Change	0.99%	25.53%	0.29%
TOTAL LIABILITIES
Total Short-Term Liabilities	$673.3M	$673.3M	$443.9M
Total Long-Term Liabilities	$1.281B	$1.973B	$1.269B
Total Liabilities	$1.954B	$3.247B	$1.712B
YoY Change	14.13%	6.29%	9.13%
SHAREHOLDERS EQUITY
Retained Earnings	$246.1M		$161.0M
YoY Change	52.85%		69.41%
Common Stock	$526.0K		$526.0K
YoY Change	0.0%		0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$18.50M		$18.13M
YoY Change	2.04%		25.08%
Treasury Stock Shares	285.5K shares		314.7K shares
Shareholders Equity	$1.960B	$1.960B	$1.888B
YoY Change
Total Liabilities & Shareholders Equity	$5.207B	$5.207B	$4.943B
YoY Change	5.34%	5.34%	6.65%

Cashflow Statement

Concept	2017 Q4	2017	2016 Q4
OPERATING ACTIVITIES
Net Income	$47.12M	$163.0M	$42.32M
YoY Change	11.35%	16.35%	7.94%
Depreciation, Depletion And Amortization	$38.60M	$151.9M	$37.30M
YoY Change	3.49%	5.63%	8.43%
Cash From Operating Activities	-$48.60M	$253.8M	$9.200M
YoY Change	-628.26%	-12.66%	-84.25%
INVESTING ACTIVITIES
Capital Expenditures	-$107.3M	$356.4M	-$77.80M
YoY Change	37.92%	15.3%	-17.76%
Acquisitions
YoY Change
Other Investing Activities	$0.00	-$618.0K	$0.00
YoY Change		-223.6%
Cash From Investing Activities	-$107.3M	-$355.7M	-$77.80M
YoY Change	37.92%	15.28%	-17.76%
FINANCING ACTIVITIES
Cash Dividend Paid		$87.95M
YoY Change		20.14%
Common Stock Issuance & Retirement, Net		$13.06M
YoY Change		-34.88%
Debt Paid & Issued, Net		$0.00
YoY Change
Cash From Financing Activities	163.5M	$101.7M	78.70M
YoY Change	107.75%	236.51%	-650.35%
NET CHANGE
Cash From Operating Activities	-48.60M	$253.8M	9.200M
Cash From Investing Activities	-107.3M	-$355.7M	-77.80M
Cash From Financing Activities	163.5M	$101.7M	78.70M
Net Change In Cash	7.600M	-$250.0K	10.10M
YoY Change	-24.75%	-102.04%	-120.0%
FREE CASH FLOW
Cash From Operating Activities	-$48.60M	$253.8M	$9.200M
Capital Expenditures	-$107.3M	$356.4M	-$77.80M
Free Cash Flow	$58.70M	-$102.6M	$87.00M
YoY Change	-32.53%	454.92%	-43.14%

Facts In Submission

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CY2017	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2017	dei	Entity Registrant Name EntityRegistrantName	ONE Gas, Inc.
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CY2016Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	1038568000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	83138000	USD
CY2015	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	63789000	USD
CY2016	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	86788000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	92393000	USD
CY2016Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1190711000	USD
CY2017Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	797339000	USD
CY2015	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	7349000	USD
CY2016	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	10541000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	9255000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	152143000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	197394000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	23094000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	24712000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	96900000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	96600000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	5716000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	2984000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	USD
CY2017Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1038568000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	599945000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	599945000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	186207000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	106285000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	990682000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	677249000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets And Liabilities DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities	13822000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets And Liabilities DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities	13805000	USD
CY2015	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-47494000	USD
CY2016	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-40912000	USD
CY2017	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-42591000	USD
CY2015	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-1962000	USD
CY2016	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-3316000	USD
CY2017	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-4597000	USD
CY2017	us-gaap	Defined Benefit Plan Amount And Timing Of Assets Expected To Be Returned To Employer During Following12 Month Period DefinedBenefitPlanAmountAndTimingOfAssetsExpectedToBeReturnedToEmployerDuringFollowing12MonthPeriod	0
CY2017	us-gaap	Defined Benefit Plan Amounts Recognized In Other Comprehensive Income Loss Net Gain Loss Before Tax DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax	0	USD
CY2016	us-gaap	Defined Benefit Plan Benefits Paid DefinedBenefitPlanBenefitsPaid	35700000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Benefits Paid DefinedBenefitPlanBenefitsPaid	18100000	USD
CY2017	us-gaap	Defined Benefit Plan Benefits Paid DefinedBenefitPlanBenefitsPaid	46700000	USD
CY2016	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed For Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear	0.0725
CY2017	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed For Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear	0.0700
CY2017	us-gaap	Defined Benefit Plan Narrative Description Of Basis Used To Determine Overall Expected Long Term Rate Of Return On Assets Assumption DefinedBenefitPlanNarrativeDescriptionOfBasisUsedToDetermineOverallExpectedLongTermRateOfReturnOnAssetsAssumption	We determine our overall expected long-term rate of return on plan assets, based on our review of historical returns and economic growth models. As of December 31, 2014, we updated our assumed mortality rates to incorporate the new set of mortality tables issued by the Society of Actuaries in October 2014. We determine our discount rates annually. We estimate our discount rate based upon a comparison of the expected cash flows associated with our future payments under our defined benefit pension and other postemployment obligations to a hypothetical bond portfolio created using high-quality bonds that closely match expected cash flows. Bond portfolios are developed by selecting a bond for each of the next 60 years based on the maturity dates of the bonds. Bonds selected to be included in the portfolios are only those rated by Moody’s as AA- or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.
CY2017	us-gaap	Defined Benefit Plan Target Plan Asset Allocations DefinedBenefitPlanTargetPlanAssetAllocations	1
CY2016	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate DefinedBenefitPlanUltimateHealthCareCostTrendRate	0.0500
CY2017	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate DefinedBenefitPlanUltimateHealthCareCostTrendRate	0.0500
CY2016Q4	us-gaap	Defined Benefit Plan Year That Rate Reaches Ultimate Trend Rate DefinedBenefitPlanYearThatRateReachesUltimateTrendRate	2022
CY2017Q4	us-gaap	Defined Benefit Plan Year That Rate Reaches Ultimate Trend Rate DefinedBenefitPlanYearThatRateReachesUltimateTrendRate	2023
CY2015	us-gaap	Dilutive Securities DilutiveSecurities	0	USD
CY2016	us-gaap	Dilutive Securities DilutiveSecurities	0	USD
CY2017	us-gaap	Dilutive Securities DilutiveSecurities	0	USD
CY2015	us-gaap	Dividends Common Stock DividendsCommonStock	62826000	USD
CY2016	us-gaap	Dividends Common Stock DividendsCommonStock	73209000	USD
CY2017	us-gaap	Dividends Common Stock DividendsCommonStock	87951000	USD
CY2015	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.26
CY2016Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.23
CY2016Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.39
CY2016Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.24
CY2016Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.81
CY2016	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.67
CY2017Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.45
CY2017Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.39
CY2016	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	8600000	USD
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.36
CY2017Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.90
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.10
CY2015	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.24
CY2016Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.22
CY2016Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.38
CY2016Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.24
CY2016Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
CY2016	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.65
CY2017Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.44
CY2017Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.39
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.36
CY2017Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.89
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.08
CY2015	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2016	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2015	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	3500000	USD
CY2016	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4300000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	3000000	USD
CY2015	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	-13709000	USD
CY2016	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	-9022000	USD
CY2017	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	-9516000	USD
CY2016Q4	us-gaap	Goodwill Goodwill	157953000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	157953000	USD
CY2015	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2016	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2017	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2015	us-gaap	Gross Profit GrossProfit	841733000	USD
CY2016	us-gaap	Gross Profit GrossProfit	885435000	USD
CY2017	us-gaap	Gross Profit GrossProfit	925132000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	192009000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	225338000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	256138000	USD
CY2015	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	72979000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	85243000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	93143000	USD
CY2015	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	67203000	USD
CY2016	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	78868000	USD
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	89648000	USD
CY2015	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-338000	USD
CY2016	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-783000	USD
CY2017	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-8000	USD
CY2015	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6114000	USD
CY2016	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	7158000	USD
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6503000	USD
CY2015	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-5423000	USD
CY2016	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-35702000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-1389000	USD
CY2015	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-59635000	USD
CY2016	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	27596000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	1945000	USD
CY2015	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	5451000	USD
CY2016	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-8539000	USD
CY2017	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	7127000	USD
CY2015	us-gaap	Increase Decrease In Customer Deposits IncreaseDecreaseInCustomerDeposits	322000	USD
CY2016	us-gaap	Increase Decrease In Customer Deposits IncreaseDecreaseInCustomerDeposits	884000	USD
CY2017	us-gaap	Increase Decrease In Customer Deposits IncreaseDecreaseInCustomerDeposits	-398000	USD
CY2015	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-4923000	USD
CY2016	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-37480000	USD
CY2017	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	0	USD
CY2015	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	1000	USD
CY2016	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-19000	USD
CY2017	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-78000	USD
CY2015	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-43147000	USD
CY2016	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-16721000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	4722000	USD
CY2015	us-gaap	Increase Decrease In Materials And Supplies IncreaseDecreaseInMaterialsAndSupplies	5814000	USD
CY2016	us-gaap	Increase Decrease In Materials And Supplies IncreaseDecreaseInMaterialsAndSupplies	759000	USD
CY2017	us-gaap	Increase Decrease In Materials And Supplies IncreaseDecreaseInMaterialsAndSupplies	5588000	USD
CY2015	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-7562000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-33141000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	10347000	USD
CY2015	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-15033000	USD
CY2016	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-25666000	USD
CY2017	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-118095000	USD
CY2015	us-gaap	Increase Decrease In Property And Other Taxes Payable IncreaseDecreaseInPropertyAndOtherTaxesPayable	-7493000	USD
CY2016	us-gaap	Increase Decrease In Property And Other Taxes Payable IncreaseDecreaseInPropertyAndOtherTaxesPayable	5322000	USD
CY2017	us-gaap	Increase Decrease In Property And Other Taxes Payable IncreaseDecreaseInPropertyAndOtherTaxesPayable	-1247000	USD
CY2015	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-105886000	USD
CY2016	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	80028000	USD
CY2017	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	15147000	USD
CY2015	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-50658000	USD
CY2016	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	49472000	USD
CY2017	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-29250000	USD
CY2015	us-gaap	Interest Expense InterestExpense	44570000	USD
CY2016	us-gaap	Interest Expense InterestExpense	43739000	USD
CY2017	us-gaap	Interest Expense InterestExpense	46065000	USD
CY2015	us-gaap	Interest Paid InterestPaid	42980000	USD
CY2016	us-gaap	Interest Paid InterestPaid	42129000	USD
CY2017	us-gaap	Interest Paid InterestPaid	44436000	USD
CY2016Q4	us-gaap	Interest Payable Current InterestPayableCurrent	18854000	USD
CY2017Q4	us-gaap	Interest Payable Current InterestPayableCurrent	18776000	USD
CY2017Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	5206878000	USD
CY2016Q4	us-gaap	Liabilities Current LiabilitiesCurrent	443933000	USD
CY2017Q4	us-gaap	Liabilities Current LiabilitiesCurrent	673330000	USD
CY2015	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	5000000	USD
CY2017	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	8700000	USD
CY2017Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	2100000	USD
CY2016Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	4942791000	USD
CY2016Q4	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	0	USD
CY2017Q4	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	0	USD
CY2017	us-gaap	Line Of Credit Facility Expiration Date1 LineOfCreditFacilityExpirationDate1	2022-10-01
CY2017Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	340700000	USD
CY2016Q4	us-gaap	Long Term Debt LongTermDebt	1200000000	USD
CY2017Q4	us-gaap	Long Term Debt LongTermDebt	1200000000	USD
CY2016Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1192446000	USD
CY2017Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1193257000	USD
CY2016Q4	us-gaap	Materials Supplies And Other MaterialsSuppliesAndOther	34084000	USD
CY2017Q4	us-gaap	Materials Supplies And Other MaterialsSuppliesAndOther	39672000	USD
CY2015	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-123106000	USD
CY2016	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	30220000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	101693000	USD
CY2015	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-294320000	USD
CY2016	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-308579000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-355743000	USD
CY2015	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	407916000	USD
CY2016	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	290589000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	253800000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	119030000	USD
CY2016Q1	us-gaap	Net Income Loss NetIncomeLoss	64743000	USD
CY2016Q2	us-gaap	Net Income Loss NetIncomeLoss	20300000	USD
CY2016Q3	us-gaap	Net Income Loss NetIncomeLoss	12737000	USD
CY2016Q4	us-gaap	Net Income Loss NetIncomeLoss	42315000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	140095000	USD
CY2017Q1	us-gaap	Net Income Loss NetIncomeLoss	76456000	USD
CY2017Q2	us-gaap	Net Income Loss NetIncomeLoss	20623000	USD
CY2017Q3	us-gaap	Net Income Loss NetIncomeLoss	18797000	USD
CY2017Q4	us-gaap	Net Income Loss NetIncomeLoss	47119000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	162995000	USD
CY2015	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	119030000	USD
CY2016	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	140095000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	162995000	USD
CY2016Q4	us-gaap	Net Regulatory Assets NetRegulatoryAssets	511746000	USD
CY2017Q4	us-gaap	Net Regulatory Assets NetRegulatoryAssets	-35490000	USD
CY2015	us-gaap	Operating Income Loss OperatingIncomeLoss	239129000	USD
CY2016Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	116073000	USD
CY2016Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	43621000	USD
CY2017Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	89512000	USD
CY2016Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	30892000	USD
CY2016Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	78534000	USD
CY2016	us-gaap	Operating Income Loss OperatingIncomeLoss	269120000	USD
CY2017Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	125132000	USD
CY2017Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	44052000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	299476000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	22100000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	4700000	USD
CY2017Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	40780000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	3700000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-314000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	3300000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	3300000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	3900000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	3200000	USD
CY2016Q4	us-gaap	Other Assets Current OtherAssetsCurrent	20654000	USD
CY2017Q4	us-gaap	Other Assets Current OtherAssetsCurrent	17807000	USD
CY2016Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	43773000	USD
CY2017Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	47157000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-776000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-1293000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Before Reclassifications Tax OtherComprehensiveIncomeLossBeforeReclassificationsTax	486000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Reclassifications Tax OtherComprehensiveIncomeLossBeforeReclassificationsTax	808000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	773000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-778000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-773000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	314000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	778000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-483000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	197000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	486000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax	-917000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax	-751000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax	-837000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax	-564000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax	-462000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax	-515000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansTax	-353000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansTax	-289000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansTax	-322000	USD
CY2016Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	21380000	USD
CY2017Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	21465000	USD
CY2016Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	76057000	USD
CY2017Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	87778000	USD
CY2015	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	2813000	USD
CY2016	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	1490000	USD
CY2017	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	1490000	USD
CY2015	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	263000	USD
CY2016	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	1447000	USD
CY2017	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	4217000	USD
CY2015	us-gaap	Payments For Removal Costs PaymentsForRemovalCosts	51608000	USD
CY2016	us-gaap	Payments For Removal Costs PaymentsForRemovalCosts	53430000	USD
CY2017	us-gaap	Payments For Removal Costs PaymentsForRemovalCosts	52376000	USD
CY2015	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	24122000	USD
CY2016	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	24066000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	17512000	USD
CY2015	us-gaap	Payments Of Dividends PaymentsOfDividends	62826000	USD
CY2016	us-gaap	Payments Of Dividends PaymentsOfDividends	73209000	USD
CY2017	us-gaap	Payments Of Dividends PaymentsOfDividends	87951000	USD
CY2015	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	294320000	USD
CY2016	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	309071000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	356361000	USD
CY2016Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	303507000	USD
CY2017Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	172938000	USD
CY2017Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2017Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	50000000	shares
CY2015	us-gaap	Prior Period Reclassification Adjustment PriorPeriodReclassificationAdjustment	13700000	USD
CY2016	us-gaap	Prior Period Reclassification Adjustment PriorPeriodReclassificationAdjustment	9000000	USD
CY2017	us-gaap	Proceeds And Excess Tax Benefit From Sharebased Compensation ProceedsAndExcessTaxBenefitFromSharebasedCompensation	5200000	USD
CY2015	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	7051000	USD
CY2016	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	4017000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	4457000	USD
CY2015	us-gaap	Proceeds From Repayments Of Commercial Paper ProceedsFromRepaymentsOfCommercialPaper	-29500000	USD
CY2016	us-gaap	Proceeds From Repayments Of Commercial Paper ProceedsFromRepaymentsOfCommercialPaper	132500000	USD
CY2017	us-gaap	Proceeds From Repayments Of Commercial Paper ProceedsFromRepaymentsOfCommercialPaper	212215000	USD
CY2015	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2016	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	492000	USD
CY2017	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	618000	USD
CY2015	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	4520000	USD
CY2016	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	5427000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	7323000	USD
CY2016Q4	us-gaap	Public Utilities Inventory PublicUtilitiesInventory	125432000	USD
CY2017Q4	us-gaap	Public Utilities Inventory PublicUtilitiesInventory	130154000	USD
CY2016Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1672548000	USD
CY2017Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1706327000	USD
CY2016Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	3731620000	USD
CY2017Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	4007585000	USD
CY2016Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	5404168000	USD
CY2017Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	5713912000	USD
CY2017Q4	us-gaap	Ratio Of Indebtedness To Net Capital1 RatioOfIndebtednessToNetCapital1	0.44
CY2016Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	290944000	USD
CY2017Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	298768000	USD
CY2016	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-462000	USD
CY2017	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-515000	USD
CY2015	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	1547692000	USD
CY2016Q1	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	508364000	USD
CY2016Q2	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	245923000	USD
CY2016Q3	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	232191000	USD
CY2016Q4	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	440754000	USD
CY2016	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	1427232000	USD
CY2017Q1	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	550408000	USD
CY2017	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	1539633000	USD
CY2016	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	417142000	USD
CY2016Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	440522000	USD
CY2017Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	405189000	USD
CY2016	us-gaap	Segment Reporting Disclosure Of Major Customers SegmentReportingDisclosureOfMajorCustomers	0
CY2017	us-gaap	Segment Reporting Disclosure Of Major Customers SegmentReportingDisclosureOfMajorCustomers	0
CY2015	us-gaap	Share Based Compensation ShareBasedCompensation	9187000	USD
CY2017	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	416542000	USD
CY2017Q2	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	279689000	USD
CY2017Q3	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	247142000	USD
CY2017Q4	us-gaap	Regulated Operating Revenue Gas RegulatedOperatingRevenueGas	462394000	USD
CY2015	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	55105000	USD
CY2016	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	55344000	USD
CY2017	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	57225000	USD
CY2016Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	83146000	USD
CY2017Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	88180000	USD
CY2016Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	0	USD
CY2017Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	519421000	USD
CY2016Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	161021000	USD
CY2017Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	246121000	USD
CY2015	us-gaap	Segment Reporting Disclosure Of Major Customers SegmentReportingDisclosureOfMajorCustomers	0
CY2016	us-gaap	Share Based Compensation ShareBasedCompensation	11219000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	8876000	USD
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	500000	shares
CY2017Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	0	USD
CY2016Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0095
CY2017Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0155
CY2015	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	14663000	USD
CY2016	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	4219000	USD
CY2017	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	4193000	USD
CY2017Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000	USD
CY2014Q4	us-gaap	Stockholders Equity StockholdersEquity	1794037000	USD
CY2015Q4	us-gaap	Stockholders Equity StockholdersEquity	1841555000	USD
CY2016Q4	us-gaap	Stockholders Equity StockholdersEquity	1888280000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	1960209000	USD
CY2016Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	314745	shares
CY2017Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	285489	shares
CY2016Q4	us-gaap	Treasury Stock Value TreasuryStockValue	18126000	USD
CY2017Q4	us-gaap	Treasury Stock Value TreasuryStockValue	18496000	USD
CY2015	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	24122000	USD
CY2016	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	24066000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	17512000	USD
CY2016Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	143200000	USD
CY2017Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	138500000	USD
CY2015	us-gaap	Utilities Operating Expense UtilitiesOperatingExpense	602604000	USD
CY2016	us-gaap	Utilities Operating Expense UtilitiesOperatingExpense	616315000	USD
CY2017	us-gaap	Utilities Operating Expense UtilitiesOperatingExpense	625656000	USD
CY2015	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	133023000	USD
CY2016	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	143829000	USD
CY2017	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	151889000	USD
CY2015	us-gaap	Utilities Operating Expense Gas And Petroleum Purchased UtilitiesOperatingExpenseGasAndPetroleumPurchased	705959000	USD
CY2016	us-gaap	Utilities Operating Expense Gas And Petroleum Purchased UtilitiesOperatingExpenseGasAndPetroleumPurchased	541797000	USD
CY2017	us-gaap	Utilities Operating Expense Gas And Petroleum Purchased UtilitiesOperatingExpenseGasAndPetroleumPurchased	614501000	USD
CY2015	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	414476000	USD
CY2015	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	676000	shares
CY2016	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	510000	shares
CY2017	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	452000	shares
CY2015	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53254000	shares
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52963000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52979000	shares
CY2015	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52578000	shares
CY2016	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52453000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52527000	shares
CY2017	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Derivatives and Risk Management Activities</font><font style="font-family:inherit;font-size:10pt;"> - We record all derivative instruments at fair value, with the exception of normal purchases and normal sales that are expected to result in physical delivery. The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and, if so, the reason for holding it, or if regulatory rulings require a different accounting treatment.</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">If certain conditions are met, we may elect to designate a derivative instrument as a hedge of exposure to changes in fair values or cash flows.</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The table below summarizes the various ways in which we account for our derivative instruments and the impact on our consolidated financial statements:</font></div><div style="line-height:120%;text-align:center;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;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="5" rowspan="1"></td></tr><tr><td style="width:23%;" rowspan="1" colspan="1"></td><td style="width:3%;" rowspan="1" colspan="1"></td><td style="width:35%;" rowspan="1" colspan="1"></td><td style="width:3%;" rowspan="1" colspan="1"></td><td style="width:36%;" rowspan="1" colspan="1"></td></tr><tr><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:9pt;"><font style="font-family:inherit;font-size:9pt;"> </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:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;"> </font></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1"><div style="text-align:center;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;font-weight:bold;">Recognition and Measurement</font></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:2px 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:9pt;"><font style="font-family:inherit;font-size:9pt;font-weight:bold;">Accounting Treatment</font></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;"> </font></div></td><td style="vertical-align:bottom;border-bottom:2px 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:9pt;"><font style="font-family:inherit;font-size:9pt;font-weight:bold;">Balance Sheet</font></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;"> </font></div></td><td style="vertical-align:bottom;border-bottom:2px 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:9pt;"><font style="font-family:inherit;font-size:9pt;font-weight:bold;">Income Statement</font></div></td></tr><tr><td style="vertical-align:top;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="vertical-align:top;text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;vertical-align:top;">Normal purchases and</font></div><div style="vertical-align:top;text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;vertical-align:top;">normal sales</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">-</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">Fair value not recorded</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">-</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">Change in fair value not recognized in earnings</font></div></td></tr><tr><td style="vertical-align:top;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">Mark-to-market</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">-</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">Recorded at fair value</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:right;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">-</font></div></td><td style="vertical-align:top;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;" rowspan="1" colspan="1"><div style="text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">Change in fair value recognized in, and</font></div><div style="text-align:left;font-size:9pt;"><font style="font-family:inherit;font-size:9pt;">recoverable through, the purchased-gas cost adjustment mechanisms</font></div></td></tr></table></div></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We have not elected to formally designate any of our derivative instruments as hedges. Gains or losses associated with the fair value of commodity derivative instruments entered into by us are included in, and recoverable through, the purchased-gas cost adjustment mechanisms.</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">See Note 7 for additional information regarding our fair value measurements and hedging activities using derivatives.</font></div></div>
CY2017	us-gaap	Use Of Estimates UseOfEstimates	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Use of Estimates</font><font style="font-family:inherit;font-size:10pt;"> - The preparation of our consolidated financial statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amount of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements. These estimates and assumptions also affect the reported amounts of revenue and expenses during the reporting period. Items that may be estimated include, but are not limited to, the economic useful life of assets, fair value of assets and liabilities, provisions for doubtful accounts receivable, unbilled revenues for natural gas delivered but for which meters have not been read, natural gas purchased but for which no invoice has been received, provision for income taxes, including any deferred income tax valuation allowances, the results of litigation and various other recorded or disclosed amounts.</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We evaluate these estimates on an ongoing basis using historical experience and other methods we consider reasonable based on the particular circumstances. Nevertheless, actual results may differ significantly from the estimates. Any effects on our financial position or results of operations from revisions to these estimates are recorded in the period when the facts that give rise to the revision become known.</font></div></div>

Files In Submission

Name	View Source	Status
0001587732-18-000014-index-headers.html	Edgar Link	pending
0001587732-18-000014-index.html	Edgar Link	pending
0001587732-18-000014.txt	Edgar Link	pending
0001587732-18-000014-xbrl.zip	Edgar Link	pending
a2017performancegraph.jpg	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
ogs-20171231.xml	Edgar Link	completed
ogs-20171231.xsd	Edgar Link	pending
ogs-20171231_cal.xml	Edgar Link	unprocessable
ogs-20171231_def.xml	Edgar Link	unprocessable
ogs-20171231_lab.xml	Edgar Link	unprocessable
ogs-20171231_pre.xml	Edgar Link	unprocessable
ogs10-k2017exhibit1011.htm	Edgar Link	pending
ogs10-k2017exhibit1014.htm	Edgar Link	pending
ogs10-k2017exhibit1015.htm	Edgar Link	pending
ogs10-k2017exhibit1028.htm	Edgar Link	pending
ogs10-k2017exhibit108.htm	Edgar Link	pending
ogs10-k2017exhibit121.htm	Edgar Link	pending
ogs10-k2017exhibit211.htm	Edgar Link	pending
ogs10-k2017exhibit231.htm	Edgar Link	pending
ogs10-k2017exhibit311.htm	Edgar Link	pending
ogs10-k2017exhibit312.htm	Edgar Link	pending
ogs10-k2017exhibit321.htm	Edgar Link	pending
ogs10-k2017exhibit322.htm	Edgar Link	pending
onegas10-k2017.htm	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
R14.htm	Edgar Link	pending
R15.htm	Edgar Link	pending
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R19.htm	Edgar Link	pending
R2.htm	Edgar Link	pending
R20.htm	Edgar Link	pending
R21.htm	Edgar Link	pending
R22.htm	Edgar Link	pending
R23.htm	Edgar Link	pending
R24.htm	Edgar Link	pending
R25.htm	Edgar Link	pending
R26.htm	Edgar Link	pending
R27.htm	Edgar Link	pending
R28.htm	Edgar Link	pending
R29.htm	Edgar Link	pending
R3.htm	Edgar Link	pending
R30.htm	Edgar Link	pending
R31.htm	Edgar Link	pending
R32.htm	Edgar Link	pending
R33.htm	Edgar Link	pending
R34.htm	Edgar Link	pending
R35.htm	Edgar Link	pending
R36.htm	Edgar Link	pending
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R38.htm	Edgar Link	pending
R39.htm	Edgar Link	pending
R4.htm	Edgar Link	pending
R40.htm	Edgar Link	pending
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R44.htm	Edgar Link	pending
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R46.htm	Edgar Link	pending
R47.htm	Edgar Link	pending
R5.htm	Edgar Link	pending
R6.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$OGS
ONE Gas, Inc. Stock $ogs

2017 Q4 Form 10-K Financial Statement

#000158773218000014 Filed on February 22, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$OGS ONE Gas, Inc. Stock $ogs

2017 Q4 Form 10-K Financial Statement

#000158773218000014 Filed on February 22, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$OGS
ONE Gas, Inc. Stock $ogs