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  <us-gaap:CollaborativeArrangementDisclosureTextBlock contextRef="c00004">Note 10 - Change in Ownership Interest
Gas Management constructed a gathering pipeline for $203.5 million and contributed the asset to Rendezvous Gas Services LLC (Rendezvous). Gas Management's ownership interest increased from 50% to 78%. As a result, common stock was reduced by $31.6 million and noncontrolling interest increased by $28.5 million. Rendezvous operates gas-gathering facilities for Pinedale Anticline and Jonah field producers for delivery to various interstate pipelines.</us-gaap:CollaborativeArrangementDisclosureTextBlock>
  <!--Entity Voluntary Filers-->
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  <!--Change in cash and cash equivalents-->
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  <!--Change in short-term debt-->
  <us-gaap:ProceedsFromRepaymentsOfShortTermDebt unitRef="u000" decimals="-5" contextRef="c00002">-109500000</us-gaap:ProceedsFromRepaymentsOfShortTermDebt>
  <!--Changes in operating assets and liabilities-->
  <us-gaap:IncreaseDecreaseInOperatingCapital unitRef="u000" decimals="-5" contextRef="c00004">116800000</us-gaap:IncreaseDecreaseInOperatingCapital>
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  <us-gaap:IncreaseDecreaseInOperatingCapital unitRef="u000" decimals="-5" contextRef="c00002">-77800000</us-gaap:IncreaseDecreaseInOperatingCapital>
  <!--Distributions from unconsolidated affiliates and other-->
  <us-gaap:EquityMethodInvestmentDividendsOrDistributions unitRef="u000" decimals="-5" contextRef="c00004">900000</us-gaap:EquityMethodInvestmentDividendsOrDistributions>
  <!--Distributions from unconsolidated affiliates and other-->
  <us-gaap:EquityMethodInvestmentDividendsOrDistributions unitRef="u000" decimals="-5" contextRef="c00002">700000</us-gaap:EquityMethodInvestmentDividendsOrDistributions>
  <!--Share-based compensation-->
  <us-gaap:ShareBasedCompensation unitRef="u000" decimals="-5" contextRef="c00004">12200000</us-gaap:ShareBasedCompensation>
  <!--Share-based compensation-->
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  <us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding unitRef="u001" decimals="0" contextRef="c00005">176.1</us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding>
  <!--Used in diluted calculation-->
  <us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding unitRef="u001" decimals="0" contextRef="c00006">176.3</us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding>
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  <us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding unitRef="u001" decimals="0" contextRef="c00004">176.0</us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding>
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  <us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding unitRef="u001" decimals="0" contextRef="c00002">176.3</us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding>
  <!--Amendment Flag-->
  <dei:AmendmentFlag contextRef="c00004">true</dei:AmendmentFlag>
  <!--Long-term debt issued, net of issuance costs-->
  <us-gaap:ProceedsFromIssuanceOfLongTermDebt unitRef="u000" decimals="-5" contextRef="c00004">49900000</us-gaap:ProceedsFromIssuanceOfLongTermDebt>
  <!--Long-term debt issued, net of issuance costs-->
  <us-gaap:ProceedsFromIssuanceOfLongTermDebt unitRef="u000" decimals="-5" contextRef="c00002">1491700000</us-gaap:ProceedsFromIssuanceOfLongTermDebt>
  <!--Investment in unconsolidated affiliates-->
  <us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures unitRef="u000" decimals="-5" contextRef="c00000">70700000</us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures>
  <!--Investment in unconsolidated affiliates-->
  <us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures unitRef="u000" decimals="-5" contextRef="c00003">68400000</us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures>
  <!--Net Property, Plant and Equipment-->
  <us-gaap:PropertyPlantAndEquipmentNet unitRef="u000" decimals="-5" contextRef="c00000">7349500000</us-gaap:PropertyPlantAndEquipmentNet>
  <!--Net Property, Plant and Equipment-->
  <us-gaap:PropertyPlantAndEquipmentNet unitRef="u000" decimals="-5" contextRef="c00003">7133000000</us-gaap:PropertyPlantAndEquipmentNet>
  <!--Diluted-->
  <us-gaap:EarningsPerShareDiluted unitRef="u002" decimals="0" contextRef="c00005">0.44</us-gaap:EarningsPerShareDiluted>
  <!--Diluted-->
  <us-gaap:EarningsPerShareDiluted unitRef="u002" decimals="0" contextRef="c00006">0.98</us-gaap:EarningsPerShareDiluted>
  <!--Diluted-->
  <us-gaap:EarningsPerShareDiluted unitRef="u002" decimals="0" contextRef="c00004">0.82</us-gaap:EarningsPerShareDiluted>
  <!--Diluted-->
  <us-gaap:EarningsPerShareDiluted unitRef="u002" decimals="0" contextRef="c00002">2.03</us-gaap:EarningsPerShareDiluted>
  <!--Net mark-to-market gain (loss) on basis-only swaps-->
  <us-gaap:UnrealizedGainLossOnDerivatives unitRef="u000" decimals="-5" contextRef="c00005">-27800000</us-gaap:UnrealizedGainLossOnDerivatives>
  <!--Net mark-to-market gain (loss) on basis-only swaps-->
  <us-gaap:UnrealizedGainLossOnDerivatives unitRef="u000" decimals="-5" contextRef="c00006">16300000</us-gaap:UnrealizedGainLossOnDerivatives>
  <!--Net mark-to-market gain (loss) on basis-only swaps-->
  <us-gaap:UnrealizedGainLossOnDerivatives unitRef="u000" decimals="-5" contextRef="c00004">-162700000</us-gaap:UnrealizedGainLossOnDerivatives>
  <!--Net mark-to-market gain (loss) on basis-only swaps-->
  <us-gaap:UnrealizedGainLossOnDerivatives unitRef="u000" decimals="-5" contextRef="c00002">30000000</us-gaap:UnrealizedGainLossOnDerivatives>
  <!--Note 2 - Basis of...-->
  <us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock contextRef="c00004">Note 2 - Basis of Presentation of Interim Consolidated Financial Statements
The interim condensed consolidated financial statements contain the accounts of Questar and its majority-owned or controlled subsidiaries. The condensed consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (GAAP) and with the instructions for quarterly reports on Form 10-Q and Regulations S-X and S-K. All significant intercompany accounts and transactions have been eliminated in consolidation.
On January 1, 2009, Questar adopted Statement of Financial Accounting Standards (SFAS) 160 "Noncontrolling Interests in Consolidated Financial Statements, an amendment of ARB No. 51." SFAS 160 requires noncontrolling interests, previously known as minority interest, in a subsidiary be clearly identified, labeled, and presented in the consolidated financial statements separate from the parent's equity; the amount of consolidated net income attributable to the parent and to the noncontrolling interest be clearly identified and presented in the consolidated income statement; changes in a parent's ownership interest while the parent retains its controlling financial interest in its subsidiary be accounted for consistently; and any retained noncontrolling equity investment in a former subsidiary be initially measured at fair value. The provisions of SFAS 160 are applied prospectively from the date of adoption, except for the presentation and disclosure requirements, which are applied retrospectively for all periods presented.
The condensed consolidated financial statements reflect all normal, recurring adjustments and accruals that are, in the opinion of management, necessary for a fair presentation of financial position and results of operations for the interim periods presented. Interim condensed consolidated financial statements do not include all of the information and notes required by GAAP for audited annual consolidated financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2008. Certain reclassifications were made to prior-period financial statements to conform with the current presentation.
The preparation of the condensed consolidated financial statements and notes in conformity with GAAP requires that management make estimates and assumptions that affect the amounts of revenues, expenses, assets and liabilities, and disclosure of contingent assets and liabilities. Actual results could differ from estimates. The results of operations for the three months and six months ended June 30, 2009, are not necessarily indicative of the results that may be expected for the year ending December 31, 2009.
The condensed consolidated financial statements reflect management's consideration of known subsequent events as of August 4, 2009, the date that the consolidated financial statements were issued.
All dollar and share amounts in this quarterly report on Form 10-Q are in millions, except per-share information and where otherwise noted.</us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock>
  <!--Entity Well-known Seasoned Issuer-->
  <dei:EntityWellKnownSeasonedIssuer contextRef="c00004">Yes</dei:EntityWellKnownSeasonedIssuer>
  <!--Common stock repurchased-->
  <us-gaap:PaymentsForRepurchaseOfCommonStock unitRef="u000" decimals="-5" contextRef="c00004">5600000</us-gaap:PaymentsForRepurchaseOfCommonStock>
  <!--Common stock repurchased-->
  <us-gaap:PaymentsForRepurchaseOfCommonStock unitRef="u000" decimals="-5" contextRef="c00002">14000000</us-gaap:PaymentsForRepurchaseOfCommonStock>
  <!--Property, plant and equipment-->
  <us-gaap:PaymentsToAcquirePropertyPlantAndEquipment unitRef="u000" decimals="-5" contextRef="c00004">-699400000</us-gaap:PaymentsToAcquirePropertyPlantAndEquipment>
  <!--Property, plant and equipment-->
  <us-gaap:PaymentsToAcquirePropertyPlantAndEquipment unitRef="u000" decimals="-5" contextRef="c00002">-1403300000</us-gaap:PaymentsToAcquirePropertyPlantAndEquipment>
  <!--Purchase-gas adjustment-->
  <us-gaap:DeferredGasPurchasesCurrent unitRef="u000" decimals="-5" contextRef="c00000">48600000</us-gaap:DeferredGasPurchasesCurrent>
  <!--Purchase-gas adjustment-->
  <us-gaap:DeferredGasPurchasesCurrent unitRef="u000" decimals="-5" contextRef="c00003">45800000</us-gaap:DeferredGasPurchasesCurrent>
  <!--Entity Public Float-->
  <dei:EntityPublicFloat unitRef="u000" decimals="0" contextRef="c00001">12200000000</dei:EntityPublicFloat>
  <!--Document Type-->
  <dei:DocumentType contextRef="c00004">10-Q</dei:DocumentType>
  <!--Other investments-->
  <us-gaap:PaymentsToAcquireOtherProductiveAssets unitRef="u000" decimals="-5" contextRef="c00004">0</us-gaap:PaymentsToAcquireOtherProductiveAssets>
  <!--Other investments-->
  <us-gaap:PaymentsToAcquireOtherProductiveAssets unitRef="u000" decimals="-5" contextRef="c00002">-9000000</us-gaap:PaymentsToAcquireOtherProductiveAssets>
  <!--Fair value of derivative contracts-->
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  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeAssetsCurrent unitRef="u000" decimals="-5" contextRef="c00003">431300000</us-gaap:DerivativeAssetsCurrent>
  <!--Cash and cash equivalents + Beginning cash and cash equivalents + Ending cash and cash equivalents-->
  <us-gaap:CashAndCashEquivalentsAtCarryingValue unitRef="u000" decimals="-5" contextRef="c00000">0</us-gaap:CashAndCashEquivalentsAtCarryingValue>
  <!--Cash and cash equivalents + Beginning cash and cash equivalents + Ending cash and cash equivalents-->
  <us-gaap:CashAndCashEquivalentsAtCarryingValue unitRef="u000" decimals="-5" contextRef="c00003">23900000</us-gaap:CashAndCashEquivalentsAtCarryingValue>
  <!--Cash and cash equivalents + Beginning cash and cash equivalents + Ending cash and cash equivalents-->
  <us-gaap:CashAndCashEquivalentsAtCarryingValue unitRef="u000" decimals="-5" contextRef="c00007">14200000</us-gaap:CashAndCashEquivalentsAtCarryingValue>
  <!--Cash and cash equivalents + Beginning cash and cash equivalents + Ending cash and cash equivalents-->
  <us-gaap:CashAndCashEquivalentsAtCarryingValue unitRef="u000" decimals="-6" contextRef="c00001">0</us-gaap:CashAndCashEquivalentsAtCarryingValue>
  <!--Used in basic calculation-->
  <us-gaap:WeightedAverageNumberOfSharesOutstandingBasic unitRef="u001" decimals="0" contextRef="c00005">174.1</us-gaap:WeightedAverageNumberOfSharesOutstandingBasic>
  <!--Used in basic calculation-->
  <us-gaap:WeightedAverageNumberOfSharesOutstandingBasic unitRef="u001" decimals="0" contextRef="c00006">172.7</us-gaap:WeightedAverageNumberOfSharesOutstandingBasic>
  <!--Used in basic calculation-->
  <us-gaap:WeightedAverageNumberOfSharesOutstandingBasic unitRef="u001" decimals="0" contextRef="c00004">173.9</us-gaap:WeightedAverageNumberOfSharesOutstandingBasic>
  <!--Used in basic calculation-->
  <us-gaap:WeightedAverageNumberOfSharesOutstandingBasic unitRef="u001" decimals="0" contextRef="c00002">172.6</us-gaap:WeightedAverageNumberOfSharesOutstandingBasic>
  <!--Questar Gas-->
  <us-gaap:RefiningAndMarketingRevenue unitRef="u000" decimals="-5" contextRef="c00005">138500000</us-gaap:RefiningAndMarketingRevenue>
  <!--Questar Gas-->
  <us-gaap:RefiningAndMarketingRevenue unitRef="u000" decimals="-5" contextRef="c00006">159500000</us-gaap:RefiningAndMarketingRevenue>
  <!--Questar Gas-->
  <us-gaap:RefiningAndMarketingRevenue unitRef="u000" decimals="-5" contextRef="c00004">544200000</us-gaap:RefiningAndMarketingRevenue>
  <!--Questar Gas-->
  <us-gaap:RefiningAndMarketingRevenue unitRef="u000" decimals="-5" contextRef="c00002">549700000</us-gaap:RefiningAndMarketingRevenue>
  <!--Entity Current Reporting Status-->
  <dei:EntityCurrentReportingStatus contextRef="c00004">Yes</dei:EntityCurrentReportingStatus>
  <!--Entity Central Index Key-->
  <dei:EntityCentralIndexKey contextRef="c00004">0000751652</dei:EntityCentralIndexKey>
  <!--NET CASH PROVIDED FROM (USED IN) FINANCING ACTIVITIES-->
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  <!--NET CASH PROVIDED FROM (USED IN) FINANCING ACTIVITIES-->
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  <!--Excess tax benefits from share-based compensation-->
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  <!--Excess tax benefits from share-based compensation-->
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  <!--Common stock issued-->
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  <!--Common stock issued-->
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  <!--Dry exploratory well expense-->
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  <!--Dry exploratory well expense-->
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  <!--Deferred income taxes - current-->
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  <!--Deferred income taxes - current-->
  <us-gaap:DeferredTaxLiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00003">130600000</us-gaap:DeferredTaxLiabilitiesCurrent>
  <!--Net income attributable to noncontrolling interest-->
  <us-gaap:NetIncomeLossAttributableToNoncontrollingInterest unitRef="u000" decimals="-5" contextRef="c00005">600000</us-gaap:NetIncomeLossAttributableToNoncontrollingInterest>
  <!--Net income attributable to noncontrolling interest-->
  <us-gaap:NetIncomeLossAttributableToNoncontrollingInterest unitRef="u000" decimals="-5" contextRef="c00006">2100000</us-gaap:NetIncomeLossAttributableToNoncontrollingInterest>
  <!--Net income attributable to noncontrolling interest-->
  <us-gaap:NetIncomeLossAttributableToNoncontrollingInterest unitRef="u000" decimals="-5" contextRef="c00004">1100000</us-gaap:NetIncomeLossAttributableToNoncontrollingInterest>
  <!--Net income attributable to noncontrolling interest-->
  <us-gaap:NetIncomeLossAttributableToNoncontrollingInterest unitRef="u000" decimals="-5" contextRef="c00002">4500000</us-gaap:NetIncomeLossAttributableToNoncontrollingInterest>
  <!--Exploration-->
  <us-gaap:ExplorationExpense unitRef="u000" decimals="-5" contextRef="c00005">8900000</us-gaap:ExplorationExpense>
  <!--Exploration-->
  <us-gaap:ExplorationExpense unitRef="u000" decimals="-5" contextRef="c00006">3800000</us-gaap:ExplorationExpense>
  <!--Exploration-->
  <us-gaap:ExplorationExpense unitRef="u000" decimals="-5" contextRef="c00004">12000000</us-gaap:ExplorationExpense>
  <!--Exploration-->
  <us-gaap:ExplorationExpense unitRef="u000" decimals="-5" contextRef="c00002">7300000</us-gaap:ExplorationExpense>
  <!--Note 6 - Fair-Val...-->
  <us-gaap:FairValueDisclosuresTextBlock contextRef="c00004">Note 6 - Fair-Value Measures
Beginning in 2008, Questar adopted the effective provisions of SFAS 157 "Fair-Value Measures." SFAS 157 defines fair value in applying GAAP, establishes a framework for measuring fair value and expands disclosures about fair-value measurements. SFAS 157 does not change existing guidance as to whether or not an instrument is carried at fair value. SFAS 157 establishes a fair-value hierarchy. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3 inputs are unobservable inputs for the asset or liability. The Level 2 fair value of derivative contracts is located in Note 7. The fair value of these derivative contracts is based on market prices posted on the NYMEX on the last trading day of the reporting period.
In February 2008, the FASB issued FSP Financial Accounting Standard (FAS) 157-2 "Partial Deferral of the Effective Date of Statement 157," which delayed the effective date of SFAS 157 for one year for certain nonfinancial assets and nonfinancial liabilities, except those recognized or disclosed at fair value in the financial statements on a recurring basis. On January 1, 2009, Questar adopted, without material impact on the consolidated financial statements, the provisions of SFAS 157 related to nonfinancial assets and nonfinancial liabilities that are not required or permitted to be measured at fair value on a recurring basis, which includes, among other things, asset retirement obligations. The valuation of asset retirement obligations is a Level 3 fair value and is discussed in Note 8.
In April 2009, the FASB issued FSP FAS 107-1 and Accounting Principles Board 28-1 "Interim Disclosures about Fair Value of Financial Instruments," which requires disclosures about fair value of financial instruments for interim periods as well as in annual financial statements. The FSP is effective for interim reporting periods ending after June 15, 2009. The following table discloses the fair value and related carrying amount of certain financial instruments not disclosed in other notes to the consolidated financial statements in this quarterly report on Form 10-Q:
	Carrying	Estimated	Carrying	Estimated
	Amount	Fair Value	Amount	Fair Value	June 30, 2009	December 31, 2008	(in millions)Financial assets				Cash and cash equivalents			$    23.9 	$    23.9 Financial liabilities				Checks outstanding in excess of cash balances	$    14.4 	$    14.4 		Short-term debt	35.5 	35.5 	231.1 	231.1 Long-term debt	2,172.2 	2,145.2 	2,122.2 	1,994.8
Cash and cash equivalents, checks outstanding in excess of cash balances and short-term debt - the carrying amount approximates fair value.
Long-term debt - the carrying amount of variable-rate debt approximates fair value. The fair value of fixed-rate debt is based on the discounted present value of cash flows using the Company's current borrowing rates.</us-gaap:FairValueDisclosuresTextBlock>
  <!--Current Fiscal Year End Date-->
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  <!--Entity Registrant Name-->
  <dei:EntityRegistrantName contextRef="c00004">Questar Corporation</dei:EntityRegistrantName>
  <!--Total Common Shareholders' Equity-->
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  <!--Total Common Shareholders' Equity-->
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  <!--Short-term debt-->
  <us-gaap:ShortTermBorrowings unitRef="u000" decimals="-5" contextRef="c00000">35500000</us-gaap:ShortTermBorrowings>
  <!--Short-term debt-->
  <us-gaap:ShortTermBorrowings unitRef="u000" decimals="-5" contextRef="c00003">231100000</us-gaap:ShortTermBorrowings>
  <!--Materials and supplies-->
  <us-gaap:OtherInventorySupplies unitRef="u000" decimals="-5" contextRef="c00000">119400000</us-gaap:OtherInventorySupplies>
  <!--Materials and supplies-->
  <us-gaap:OtherInventorySupplies unitRef="u000" decimals="-5" contextRef="c00003">106900000</us-gaap:OtherInventorySupplies>
  <!--Dividends per common share-->
  <us-gaap:CommonStockDividendsPerShareCashPaid unitRef="u002" decimals="2" contextRef="c00005">0.125</us-gaap:CommonStockDividendsPerShareCashPaid>
  <!--Dividends per common share-->
  <us-gaap:CommonStockDividendsPerShareCashPaid unitRef="u002" decimals="2" contextRef="c00006">0.1225</us-gaap:CommonStockDividendsPerShareCashPaid>
  <!--Dividends per common share-->
  <us-gaap:CommonStockDividendsPerShareCashPaid unitRef="u002" decimals="2" contextRef="c00004">0.25</us-gaap:CommonStockDividendsPerShareCashPaid>
  <!--Dividends per common share-->
  <us-gaap:CommonStockDividendsPerShareCashPaid unitRef="u002" decimals="2" contextRef="c00002">0.245</us-gaap:CommonStockDividendsPerShareCashPaid>
  <!--OPERATING INCOME-->
  <us-gaap:OperatingIncomeLoss unitRef="u000" decimals="-5" contextRef="c00005">175500000</us-gaap:OperatingIncomeLoss>
  <!--OPERATING INCOME-->
  <us-gaap:OperatingIncomeLoss unitRef="u000" decimals="-5" contextRef="c00006">284600000</us-gaap:OperatingIncomeLoss>
  <!--OPERATING INCOME-->
  <us-gaap:OperatingIncomeLoss unitRef="u000" decimals="-5" contextRef="c00004">442600000</us-gaap:OperatingIncomeLoss>
  <!--OPERATING INCOME-->
  <us-gaap:OperatingIncomeLoss unitRef="u000" decimals="-5" contextRef="c00002">593200000</us-gaap:OperatingIncomeLoss>
  <!--Net gain (loss) from asset sales-->
  <us-gaap:GainLossOnDispositionOfAssets unitRef="u000" decimals="-5" contextRef="c00005">-200000</us-gaap:GainLossOnDispositionOfAssets>
  <!--Net gain (loss) from asset sales-->
  <us-gaap:GainLossOnDispositionOfAssets unitRef="u000" decimals="-5" contextRef="c00006">3500000</us-gaap:GainLossOnDispositionOfAssets>
  <!--Net gain (loss) from asset sales-->
  <us-gaap:GainLossOnDispositionOfAssets unitRef="u000" decimals="-5" contextRef="c00004">1700000</us-gaap:GainLossOnDispositionOfAssets>
  <!--Net gain (loss) from asset sales-->
  <us-gaap:GainLossOnDispositionOfAssets unitRef="u000" decimals="-5" contextRef="c00002">3400000</us-gaap:GainLossOnDispositionOfAssets>
  <!--Depreciation, depletion and amortization-->
  <us-gaap:DepreciationAndAmortization unitRef="u000" decimals="-5" contextRef="c00005">180100000</us-gaap:DepreciationAndAmortization>
  <!--Depreciation, depletion and amortization-->
  <us-gaap:DepreciationAndAmortization unitRef="u000" decimals="-5" contextRef="c00006">115200000</us-gaap:DepreciationAndAmortization>
  <!--Depreciation, depletion and amortization-->
  <us-gaap:DepreciationAndAmortization unitRef="u000" decimals="-5" contextRef="c00004">341400000</us-gaap:DepreciationAndAmortization>
  <!--Depreciation, depletion and amortization-->
  <us-gaap:DepreciationAndAmortization unitRef="u000" decimals="-5" contextRef="c00002">225900000</us-gaap:DepreciationAndAmortization>
  <!--General and administrative-->
  <us-gaap:GeneralAndAdministrativeExpense unitRef="u000" decimals="-5" contextRef="c00005">47400000</us-gaap:GeneralAndAdministrativeExpense>
  <!--General and administrative-->
  <us-gaap:GeneralAndAdministrativeExpense unitRef="u000" decimals="-5" contextRef="c00006">45000000</us-gaap:GeneralAndAdministrativeExpense>
  <!--General and administrative-->
  <us-gaap:GeneralAndAdministrativeExpense unitRef="u000" decimals="-5" contextRef="c00004">88600000</us-gaap:GeneralAndAdministrativeExpense>
  <!--General and administrative-->
  <us-gaap:GeneralAndAdministrativeExpense unitRef="u000" decimals="-5" contextRef="c00002">87300000</us-gaap:GeneralAndAdministrativeExpense>
  <!--Note 8 - Asset Re...-->
  <us-gaap:CapitalizedCostsRelatingToOilAndGasProducingActivitiesDisclosureTextBlock contextRef="c00004">Note 8 - Asset Retirement Obligations (ARO)
Questar recognizes ARO in accordance with SFAS 143 "Accounting for Asset Retirement Obligations." SFAS 143 addresses the financial accounting and reporting of the fair value of legal obligations associated with the retirement of tangible long-lived assets. At Questar, ARO applies primarily to abandonment costs associated with gas and oil wells, production facilities and certain other properties. The fair value of retirement costs are estimated by Company personnel based on abandonment costs of similar properties (Level 3 inputs under the provisions of SFAS 157) available to field operations and depreciated over the life of the related assets. Revisions to ARO estimates result from changes in expected cash flows or material changes in estimated retirement costs. Income or expense resulting from the settlement of ARO liabilities is included in other income on the Consolidated Statements of Income. The ARO liability is adjusted to present value each period through an accretion calculation using a credit-adjusted risk-free interest rate. Changes in ARO were as follows:
Level 3 fair value 	2009	2008
	(in millions)
ARO liability at January 1, 	$175.6 	$149.1 Accretion 	5.5 	4.7 Liabilities incurred	1.4 	7.9 Revisions	2.4 	1.5 Liabilities settled	(1.5)	(0.8)ARO liability at June 30, 	$183.4 	$162.4
Wexpro collects from Questar Gas and deposits in trust certain funds related to estimated ARO costs. The funds are used to satisfy retirement obligations as the properties are abandoned and recorded in other noncurrent assets on the Consolidated Balance Sheets. Trust funds are invested primarily in a money-market account with a balance of $10.8 million at June 30, 2009. The fair value of Wexpro's trust is based on asset summary statements provided by the bank holding the trust and considered Level 2 fair value measurement under the provisions of SFAS 157.</us-gaap:CapitalizedCostsRelatingToOilAndGasProducingActivitiesDisclosureTextBlock>
  <!--Note 1 - Nature o...-->
  <us-gaap:NatureOfOperations contextRef="c00004">Note 1 - Nature of Business
Questar Corporation (Questar or the Company) is a natural gas-focused energy company with five major lines of business - gas and oil exploration and production, midstream field services, energy marketing, interstate gas transportation, and retail gas distribution - which are conducted through its three principal subsidiaries:
-	Questar Market Resources, Inc. (Market Resources) is a subholding company that operates through four principal subsidiaries. Questar Exploration and Production Company (Questar E&amp;P) acquires, explores for, develops and produces natural gas, oil and NGL. Wexpro Company (Wexpro) manages, develops and produces cost-of-service reserves for gas utility affiliate Questar Gas. Questar Gas Management Company (Gas Management) provides midstream field services including natural gas-gathering and processing services for affiliates and third parties. Questar Energy Trading Company (Energy Trading) markets equity and third-party natural gas and oil, provides risk-management services and owns and operates an underground gas-storage reservoir. -	Questar Pipeline Company (Questar Pipeline) provides interstate natural gas transportation and storage and other energy services.
-	Questar Gas Company (Questar Gas) provides retail natural gas distribution services in Utah, Wyoming and Idaho.
Questar operates in the Rocky Mountain and Midcontinent regions of the United States of America and is headquartered in Salt Lake City, Utah. Shares of Questar common stock trade on the New York Stock Exchange under the symbol STR.</us-gaap:NatureOfOperations>
  <!--Other-->
  <us-gaap:ProceedsFromPaymentsForOtherFinancingActivities unitRef="u000" decimals="-5" contextRef="c00004">0</us-gaap:ProceedsFromPaymentsForOtherFinancingActivities>
  <!--Other-->
  <us-gaap:ProceedsFromPaymentsForOtherFinancingActivities unitRef="u000" decimals="-5" contextRef="c00002">1000000</us-gaap:ProceedsFromPaymentsForOtherFinancingActivities>
  <!--Deferred income taxes-->
  <us-gaap:DeferredIncomeTaxExpenseBenefit unitRef="u000" decimals="-5" contextRef="c00004">56600000</us-gaap:DeferredIncomeTaxExpenseBenefit>
  <!--Deferred income taxes-->
  <us-gaap:DeferredIncomeTaxExpenseBenefit unitRef="u000" decimals="-5" contextRef="c00002">152200000</us-gaap:DeferredIncomeTaxExpenseBenefit>
  <!--Total Equity-->
  <us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest unitRef="u000" decimals="-5" contextRef="c00000">3470900000</us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest>
  <!--Total Equity-->
  <us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest unitRef="u000" decimals="-5" contextRef="c00003">3447500000</us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest>
  <!--Accounts payable and accrued expenses-->
  <us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00000">414200000</us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent>
  <!--Accounts payable and accrued expenses-->
  <us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00003">682900000</us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent>
  <!--Checks outstanding in excess of cash balances-->
  <us-gaap:BankOverdrafts unitRef="u000" decimals="-5" contextRef="c00000">14400000</us-gaap:BankOverdrafts>
  <!--Checks outstanding in excess of cash balances-->
  <us-gaap:BankOverdrafts unitRef="u000" decimals="-5" contextRef="c00003">0</us-gaap:BankOverdrafts>
  <!--Goodwill-->
  <us-gaap:Goodwill unitRef="u000" decimals="-5" contextRef="c00000">69900000</us-gaap:Goodwill>
  <!--Goodwill-->
  <us-gaap:Goodwill unitRef="u000" decimals="-5" contextRef="c00003">70000000</us-gaap:Goodwill>
  <!--Abandonment and impairment-->
  <us-gaap:ExplorationAbandonmentAndImpairmentExpense unitRef="u000" decimals="-5" contextRef="c00005">3800000</us-gaap:ExplorationAbandonmentAndImpairmentExpense>
  <!--Abandonment and impairment-->
  <us-gaap:ExplorationAbandonmentAndImpairmentExpense unitRef="u000" decimals="-5" contextRef="c00006">14200000</us-gaap:ExplorationAbandonmentAndImpairmentExpense>
  <!--Abandonment and impairment-->
  <us-gaap:ExplorationAbandonmentAndImpairmentExpense unitRef="u000" decimals="-5" contextRef="c00004">7500000</us-gaap:ExplorationAbandonmentAndImpairmentExpense>
  <!--Abandonment and impairment-->
  <us-gaap:ExplorationAbandonmentAndImpairmentExpense unitRef="u000" decimals="-5" contextRef="c00002">16800000</us-gaap:ExplorationAbandonmentAndImpairmentExpense>
  <!--Note 5 - Capitali...-->
  <us-gaap:SuspendedWellCostsDisclosureTextBlock contextRef="c00004">Note 5 - Capitalized Exploratory Well Costs
Net changes in capitalized exploratory well costs are presented in the table below and exclude amounts that were capitalized and subsequently expensed in the first six months. All costs have been capitalized for less than one year.
	2009	2008
	(in millions)
Balance at January 1,	$ 17.0 	$1.5
Additions to capitalized exploratory well costs pending the
    determination of proved reserves	35.2 	Reclassifications to property, plant and equipment after the
    determination of proved reserves	(14.3)	(0.1)Capitalized exploratory well costs charged to expense 	(2.7)
Balance at June 30,	$ 35.2 	$1.4</us-gaap:SuspendedWellCostsDisclosureTextBlock>
  <!--Amendment Description-->
  <dei:AmendmentDescription contextRef="c00004">10-Q/A</dei:AmendmentDescription>
  <!--Dividends paid-->
  <us-gaap:PaymentsOfDividends unitRef="u000" decimals="-5" contextRef="c00004">43500000</us-gaap:PaymentsOfDividends>
  <!--Dividends paid-->
  <us-gaap:PaymentsOfDividends unitRef="u000" decimals="-5" contextRef="c00002">42400000</us-gaap:PaymentsOfDividends>
  <!--Checks outstanding in excess of cash balances-->
  <us-gaap:IncreaseDecreaseInOutstandingChecksFinancingActivities unitRef="u000" decimals="-5" contextRef="c00004">14400000</us-gaap:IncreaseDecreaseInOutstandingChecksFinancingActivities>
  <!--Checks outstanding in excess of cash balances-->
  <us-gaap:IncreaseDecreaseInOutstandingChecksFinancingActivities unitRef="u000" decimals="-5" contextRef="c00002">14400000</us-gaap:IncreaseDecreaseInOutstandingChecksFinancingActivities>
  <!--Proceeds from disposition of assets-->
  <us-gaap:ProceedsFromSaleOfProductiveAssets unitRef="u000" decimals="-5" contextRef="c00004">7900000</us-gaap:ProceedsFromSaleOfProductiveAssets>
  <!--Proceeds from disposition of assets-->
  <us-gaap:ProceedsFromSaleOfProductiveAssets unitRef="u000" decimals="-5" contextRef="c00002">33300000</us-gaap:ProceedsFromSaleOfProductiveAssets>
  <!--NET CASH PROVIDED FROM OPERATING ACTIVITIES-->
  <us-gaap:NetCashProvidedByUsedInOperatingActivities unitRef="u000" decimals="-5" contextRef="c00004">847400000</us-gaap:NetCashProvidedByUsedInOperatingActivities>
  <!--NET CASH PROVIDED FROM OPERATING ACTIVITIES-->
  <us-gaap:NetCashProvidedByUsedInOperatingActivities unitRef="u000" decimals="-5" contextRef="c00002">659200000</us-gaap:NetCashProvidedByUsedInOperatingActivities>
  <!--Other long-term liabilities-->
  <us-gaap:OtherLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">119300000</us-gaap:OtherLiabilitiesNoncurrent>
  <!--Other long-term liabilities-->
  <us-gaap:OtherLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">142700000</us-gaap:OtherLiabilitiesNoncurrent>
  <!--Long-term debt, less current portion-->
  <us-gaap:LongTermDebtNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">2129000000</us-gaap:LongTermDebtNoncurrent>
  <!--Long-term debt, less current portion-->
  <us-gaap:LongTermDebtNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">2078900000</us-gaap:LongTermDebtNoncurrent>
  <!--Prepaid expenses and other-->
  <us-gaap:PrepaidExpenseCurrent unitRef="u000" decimals="-5" contextRef="c00000">74900000</us-gaap:PrepaidExpenseCurrent>
  <!--Prepaid expenses and other-->
  <us-gaap:PrepaidExpenseCurrent unitRef="u000" decimals="-5" contextRef="c00003">55000000</us-gaap:PrepaidExpenseCurrent>
  <!--Note 13 - Recent ...-->
  <us-gaap:ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock contextRef="c00004">Note 13 - Recent Accounting Developments
In April 2009, the FASB issued FSP FAS 157-4, "Determining Fair Value When the Volume and Level of Activity for the Asset or Liability Have Significantly Decreased and Identifying Transactions That Are Not Orderly," which provides additional guidance for estimating fair value when the level of activity for the asset or liability has significantly decreased. This FSP clarifies and includes additional factors to consider in determining whether there has been a significant decrease in market activity for an asset or liability and estimating fair value when the market activity for an asset or liability has declined significantly. The scope of this FSP does not include assets and liabilities measured under Level 1 inputs. FSP FAS 157-4 is to be applied prospectively to all fair value measurements where appropriate and its provisions are in effect for interim and annual periods ending after June 15, 2009. The adoption of FSP FAS 157-4 did not have a material impact on financial position or results of operations.
In May 2009, the FASB issued SFAS 165, "Subsequent Events" to establish a general standard of accounting for and disclosure of events that occur after the close of the period but before financial statements are issued or are available to be issued. The provisions of this statement are in effect for interim and annual periods ending after June 15, 2009. The adoption of SFAS 165 did not have a material impact on financial position or results of operations.</us-gaap:ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock>
  <!--Asset retirement obligations-->
  <us-gaap:AssetRetirementObligationsNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">183400000</us-gaap:AssetRetirementObligationsNoncurrent>
  <!--Asset retirement obligations-->
  <us-gaap:AssetRetirementObligationsNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">175600000</us-gaap:AssetRetirementObligationsNoncurrent>
  <!--Current portion of long-term debt-->
  <us-gaap:LongTermDebtCurrent unitRef="u000" decimals="-5" contextRef="c00000">42000000</us-gaap:LongTermDebtCurrent>
  <!--Current portion of long-term debt-->
  <us-gaap:LongTermDebtCurrent unitRef="u000" decimals="-5" contextRef="c00003">42000000</us-gaap:LongTermDebtCurrent>
  <!--Regulatory assets-->
  <us-gaap:RegulatoryAssetsNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">23800000</us-gaap:RegulatoryAssetsNoncurrent>
  <!--Regulatory assets-->
  <us-gaap:RegulatoryAssetsNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">26300000</us-gaap:RegulatoryAssetsNoncurrent>
  <!--Total Current Assets-->
  <us-gaap:AssetsCurrent unitRef="u000" decimals="-5" contextRef="c00000">806800000</us-gaap:AssetsCurrent>
  <!--Total Current Assets-->
  <us-gaap:AssetsCurrent unitRef="u000" decimals="-5" contextRef="c00003">1185000000</us-gaap:AssetsCurrent>
  <!--Accounts receivable, net-->
  <us-gaap:AccountsReceivableNetCurrent unitRef="u000" decimals="-5" contextRef="c00000">218100000</us-gaap:AccountsReceivableNetCurrent>
  <!--Accounts receivable, net-->
  <us-gaap:AccountsReceivableNetCurrent unitRef="u000" decimals="-5" contextRef="c00003">386600000</us-gaap:AccountsReceivableNetCurrent>
  <!--Note 12 - Compreh...-->
  <us-gaap:ComprehensiveIncomeNoteTextBlock contextRef="c00004">Note 12 - Comprehensive Income	Comprehensive income is the sum of net income attributable to Questar as reported in the Consolidated Statements of Income and other comprehensive income (loss). Other comprehensive income (loss) includes changes in the market value of commodity-based derivative instruments and recognition of the under-funded position of pension and other postretirement benefit plans. Comprehensive income (loss) attributable to Questar is shown below:
	3 Months Ended June 30,	6 Months Ended June 30,
	2009	2008	2009	2008	(in millions)Net income 	$   78.5 	$174.7 	$146.2 	$362.9 Other comprehensive (loss)				  Net unrealized (loss) on derivatives	(229.6)	(501.6)	(140.0)	(812.5)  Income taxes	85.4 	190.1 	52.0 	307.9   Net other comprehensive (loss)	(144.2)	(311.5)	(88.0)	(504.6)
  Comprehensive income (loss)	(65.7)	(136.8)	58.2 	(141.7)  Comprehensive income attributable to noncontrolling interest	(0.6)	(2.1)	(1.1)	(4.5)    Total comprehensive income (loss) attributable to Questar 	($  66.3)	($138.9)	$  57.1 	($146.2)
The components of AOCI, net of income taxes, shown on the condensed Consolidated Balance Sheets are as follows:
	June 30,	December 31,
	2009	2008	Change
	(in millions)
Net unrealized income on derivatives	$ 253.6 	$ 341.6 	($88.0)
Pension liability	(129.5)	(129.5)	Postretirement benefits liability	(17.4)	(17.4)	Accumulated other comprehensive income	$106.7 	$ 194.7 	($88.0)</us-gaap:ComprehensiveIncomeNoteTextBlock>
  <!--Note 11 - Operati...-->
  <us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock contextRef="c00004">Note 11 - Operations by Line of Business
Questar's major lines of business include gas and oil exploration and production (Questar E&amp;P and Wexpro), midstream field services (Gas Management), energy marketing (Energy Trading), interstate gas transportation (Questar Pipeline), and retail gas distribution (Questar Gas). Line-of-business information is presented according to senior management's basis for evaluating performance considering differences in the nature of products, services and regulation among other factors. Following is a summary of operations by line of business:
	3 Months Ended June 30,	6 Months Ended June 30,
	2009	2008	2009	2008	(in millions)Revenues from Unaffiliated Customers		Questar E&amp;P	$298.3 	$349.4 	$   605.7 	$  649.1 Wexpro	3.4 	8.5 	5.8 	16.8 Gas Management	52.9 	72.2 	101.2 	135.3 Energy Trading and other	77.0 	192.9 	191.6 	387.4   Market Resources 	431.6 	623.0 	904.3 	1,188.6 Questar Pipeline	43.0 	43.3 	83.7 	88.0 Questar Gas	138.5 	159.5 	544.2 	549.7 Total	$613.1 	$825.8 	$1,532.2 	$1,826.3 				Revenues from Affiliated Companies 		Wexpro	$  53.3 	$  52.3 	$112.8 	$  98.7 Gas Management	6.5 	5.5 	13.2 	11.3 Energy Trading and other	77.1 	257.8 	170.3 	484.1   Market Resources 	136.9 	315.6 	296.3 	594.1 Questar Pipeline18.3 	18.7 	37.4 	38.2 Questar Gas	0.5 	2.3 	0.5 	4.3 Total	$155.7 	$336.6 	$334.2 	$636.6 				Operating Income 				Questar E&amp;P	$  88.7 	$186.8 	$212.5 	$338.8 Wexpro	29.9 	28.2 	58.8 	53.6 Gas Management	24.2 	37.8 	43.8 	70.9 Energy Trading and other	1.1 	7.1 	9.4 	19.3   Market Resources 	143.9 	259.9 	324.5 	482.6 Questar Pipeline	29.9 	23.6 	59.2 	56.1 Questar Gas	1.6 	1.1 	58.8 	54.5 Corporate	0.1 		0.1 	Total	$175.5 	$284.6 	$442.6 	$593.2 				Net Income (Loss) Attributable to Questar				Questar E&amp;P	$29.6 	$116.8 	$  14.7 	$213.3 Wexpro	19.8 	18.8 	38.6 	35.0 Gas Management	14.5 	21.7 	25.9 	40.2 Energy Trading and other	0.8 	4.8 	6.2 	12.9   Market Resources 	64.7 	162.1 	85.4 	301.4 Questar Pipeline	15.0 	12.7 	29.7 	28.6 Questar Gas	(2.0)	(2.0)	29.8 	28.6 Corporate	0.2 	(0.2)	0.2 	(0.2)Total	$77.9 	$172.6 	$145.1 	$358.4</us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock>
  <!--Note 7 - Derivati...-->
  <us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock contextRef="c00004">Note 7 a Derivative Contracts
Market Resources' subsidiaries use commodity-based derivative instruments in the normal course of business. Market Resources has established policies and procedures for managing commodity-price risks through the use of derivative instruments. The Finance and Audit Committee of the Company's Board of Directors periodically reviews the policies. On January 1, 2009, the Company adopted SFAS 161 "Disclosures about Derivative Instruments and Hedging Activities," which requires more detailed information about hedging transactions including the location and effect on the primary consolidated financial statements.
Market Resources hedges natural gas and oil prices to support rate of return and cash-flow targets and protect earnings from downward movements in commodity prices. However, these same arrangements typically limit future gains from favorable price movements. Derivative contracts are currently in place for a significant share of Questar E&amp;P-owned gas and oil production and a portion of Energy Trading gas marketing transactions. The volume of hedged production and the mix of derivative instruments are regularly evaluated and adjusted by management in response to changing market conditions. Market Resources may hedge up to 100% of forecast production from proved reserves when prices meet earnings and cash-flow objectives. Market Resources does not enter into derivative arrangements for speculative purposes.
Market Resources uses derivative instruments known as fixed-price swaps to realize a known price for a specific volume of production delivered into a regional sales point. Swap agreements do not require the physical transfer of natural gas between the parties at settlement. Swap transactions are settled in cash with one party paying the other for the net difference in prices, multiplied by the relevant volume, for the settlement period. Questar E&amp;P has also used natural gas basis-only swaps to protect cash flows and net income from widening natural gas-price basis differentials. However, natural gas basis-only swaps expose the Company to losses from narrowing natural gas price-differentials.
Market Resources enters into derivative instruments that do not have margin requirements or collateral provisions that would require funding prior to the scheduled cash settlement dates. Derivative-arrangement counterparties are normally financial institutions and energy-trading firms with investment-grade credit ratings. The Company regularly monitors and manages its exposure to counterparty risk by requiring specific minimum credit standards for all counterparties and transacting with multiple counterparties.

Under SFAS 133 "Accounting for Derivative Instruments and Hedging Activities", every derivative instrument is required to be recorded on the balance sheet as either an asset or a liability measured at its fair value. The designation of a derivative instrument as a hedge and its ability to meet the hedge accounting criteria of SFAS 133 determines how change in fair value of the derivative instrument is reflected in the consolidated financial statements. A derivative instrument qualifies for hedge accounting, if at inception, the derivative is expected to be highly effective in offsetting the underlying hedged cash flows. Generally, Market Resources' derivative instruments are matched to equity gas and oil production, thus qualifying as cash flow hedges. Changes in the fair value of effective cash flow hedges are recorded as a component of accumulated other comprehensive income (AOCI) on the Condensed Consolidated Balance Sheets and reclassified to earnings as gas and oil sales when the underlying physical transactions occur. Gas hedges are typically structured as fixed-price swaps into regional pipelines, locking in basis and hedge effectiveness. A basis-only swap does not qualify for hedge accounting treatment. Market Resources regularly reviews the effectiveness of derivative instruments. The ineffective portion of cash flow hedges and the mark to market adjustment of basis-only swaps are immediately recognized in the determination of net income.

3 Months Ended 	6 Months Ended
	June 30, 2009
	(in millions)
Effect of derivative instruments designated as hedges		Revenues 		  Fixed-price swaps increased revenues  	$178.0 	$333.1Cost Of Natural Gas And Other Products Sold		  Fixed-price swaps increased product costs   	3.3 	3.9Effect of derivative instruments not designated as hedges		Net mark-to-market (loss) on basis-only swaps 	($  27.8)	($162.7)
Contract settlements for the first half of 2009 resulted in a transfer of $153.6 million after-tax income from AOCI to the Consolidated Statements of Income. In the next twelve months $223.2 million or 88% of the $253.6 million after-tax net unrealized income on derivatives will be settled and transferred from AOCI to the Consolidated Statements of Income. The following table discloses Level 2 fair value of derivative contracts on a gross-contract basis as opposed to the net-contract basis presentation on the Condensed Consolidated Balance Sheets. The fair value of these derivative contracts is based on prices posted on the NYMEX on the last trading day of the reporting period.
Level 2 fair value 	June 30, 2009
	(in millions)
Assets
Fixed-price swaps 	$519.3 Basis-only swaps	9.0 Fair value of derivative instruments - short term	$528.3 Fixed-price swaps 	$77.2 Basis-only swaps	0.7 Fair value of derivative instruments - long term	$77.9 Liabilities	Fixed-price swaps 	$  83.6 Basis-only swaps	154.9 Fair value of derivative instruments - short term 	$238.5 Fixed-price swaps 	$109.5 Basis-only swaps	92.9 Fair value of derivative instruments - long term	$202.4
The following table sets forth Market Resources' hedged volumes and average net to the well hedge prices as of June 30, 2009:



Questar E&amp;P Equity Production
Year	Time Periods	Quantity	Average hedge price,net to the well(a)			(estimated)Gas (Bcf) Fixed-price Swaps2009	Second half	65.0	$7.652010	12 months	140.7	5.292011	12 months	58.0	5.25
Gas (Bcf) Basis-only Swaps
2009	Second half	12.8	$2.49
2010	12 months	6.7	0.952011	12 months	57.6	2.27
Oil (Mbbl) Fixed-price Swaps
2009	Second half	736	$59.03
2010	12 months	913	60.66
Energy Trading Marketing Transactions
Year	Time Periods	Quantity	Average price per MMBtuGas Sales (millions of MMBtu) Fixed-price Swaps2009	Second half 	9.6	$3.952010	12 months	1.1	5.34
Gas Purchases (millions of MMBtu) Fixed-price Swaps
2009	Second half	8.1	$3.632010	12 months	0.6	5.60(a)	The fixed-price swap price is reduced by gathering costs and adjusted for product quality to determine the net-to-the-well price</us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock>
  <!--Note 3 - Earnings...-->
  <us-gaap:EarningsPerShareTextBlock contextRef="c00004">Note 3 - Earnings Per Share (EPS)
Basic EPS is computed by dividing net income attributable to Questar by the weighted-average number of common shares outstanding during the reporting period. Diluted EPS includes the potential increase in the number of outstanding shares that could result from the exercise of in-the-money stock options. During the first quarter of 2009, the Company adopted the provisions of Financial Accounting Standards Board (FASB) Staff Position (FSP) Emerging Issues Task Force (EITF) 03-06-1 "Determining Whether Instruments Granted in Share-Based Payment Transactions Are Participating Securities." EITF 03-06-1 addresses whether instruments granted in share-based payment transactions are participating securities and therefore have a potential dilutive effect on EPS. The adoption of EITF 03-06-1 was applied retrospectively and did not have a material effect on the Company's EPS calculations. A reconciliation of the components of basic and diluted shares used in the EPS calculation follows:
	3 Months Ended June 30,	6 Months Ended June 30,
	2009	2008	2009	2008	(in millions)Weighted-average basic common shares outstanding	174.1	172.7	173.9	172.6Potential number of shares issuable under the Long-term Stock Incentive Plan	2.0	3.6	2.1	3.7Average diluted common shares outstanding	176.1	176.3	176.0	176.3</us-gaap:EarningsPerShareTextBlock>
  <!--Long-term debt repaid-->
  <us-gaap:RepaymentsOfLongTermDebt unitRef="u000" decimals="-5" contextRef="c00004">0</us-gaap:RepaymentsOfLongTermDebt>
  <!--Long-term debt repaid-->
  <us-gaap:RepaymentsOfLongTermDebt unitRef="u000" decimals="-5" contextRef="c00002">643000000</us-gaap:RepaymentsOfLongTermDebt>
  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">170400000</us-gaap:DerivativeLiabilitiesNoncurrent>
  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">69000000</us-gaap:DerivativeLiabilitiesNoncurrent>
  <!--Unbilled-gas accounts receivable-->
  <us-gaap:UnbilledContractsReceivable unitRef="u000" decimals="-5" contextRef="c00000">18500000</us-gaap:UnbilledContractsReceivable>
  <!--Unbilled-gas accounts receivable-->
  <us-gaap:UnbilledContractsReceivable unitRef="u000" decimals="-5" contextRef="c00003">95800000</us-gaap:UnbilledContractsReceivable>
  <!--Basic-->
  <us-gaap:EarningsPerShareBasic unitRef="u002" decimals="0" contextRef="c00005">0.44</us-gaap:EarningsPerShareBasic>
  <!--Basic-->
  <us-gaap:EarningsPerShareBasic unitRef="u002" decimals="0" contextRef="c00006">1.00</us-gaap:EarningsPerShareBasic>
  <!--Basic-->
  <us-gaap:EarningsPerShareBasic unitRef="u002" decimals="0" contextRef="c00004">0.83</us-gaap:EarningsPerShareBasic>
  <!--Basic-->
  <us-gaap:EarningsPerShareBasic unitRef="u002" decimals="0" contextRef="c00002">2.08</us-gaap:EarningsPerShareBasic>
  <!--Document Period End Date-->
  <dei:DocumentPeriodEndDate contextRef="c00004">2009-06-30</dei:DocumentPeriodEndDate>
  <!--NET CASH USED IN INVESTING ACTIVITIES-->
  <us-gaap:NetCashProvidedByUsedInInvestingActivities unitRef="u000" decimals="-5" contextRef="c00004">-696100000</us-gaap:NetCashProvidedByUsedInInvestingActivities>
  <!--NET CASH USED IN INVESTING ACTIVITIES-->
  <us-gaap:NetCashProvidedByUsedInInvestingActivities unitRef="u000" decimals="-5" contextRef="c00002">-1382000000</us-gaap:NetCashProvidedByUsedInInvestingActivities>
  <!--Common stock-->
  <us-gaap:CommonStockValue unitRef="u000" decimals="-5" contextRef="c00000">434500000</us-gaap:CommonStockValue>
  <!--Common stock-->
  <us-gaap:CommonStockValue unitRef="u000" decimals="-5" contextRef="c00003">451000000</us-gaap:CommonStockValue>
  <!--Gas and oil storage-->
  <us-gaap:EnergyRelatedInventoryGasStoredUnderground unitRef="u000" decimals="-5" contextRef="c00000">31500000</us-gaap:EnergyRelatedInventoryGasStoredUnderground>
  <!--Gas and oil storage-->
  <us-gaap:EnergyRelatedInventoryGasStoredUnderground unitRef="u000" decimals="-5" contextRef="c00003">85500000</us-gaap:EnergyRelatedInventoryGasStoredUnderground>
  <!--Total Operating Expenses-->
  <us-gaap:OperatingExpenses unitRef="u000" decimals="-5" contextRef="c00005">437400000</us-gaap:OperatingExpenses>
  <!--Total Operating Expenses-->
  <us-gaap:OperatingExpenses unitRef="u000" decimals="-5" contextRef="c00006">544700000</us-gaap:OperatingExpenses>
  <!--Total Operating Expenses-->
  <us-gaap:OperatingExpenses unitRef="u000" decimals="-5" contextRef="c00004">1091300000</us-gaap:OperatingExpenses>
  <!--Total Operating Expenses-->
  <us-gaap:OperatingExpenses unitRef="u000" decimals="-5" contextRef="c00002">1236500000</us-gaap:OperatingExpenses>
  <!--Cost of natural gas and other products sold (excluding operating expenses shown separately)-->
  <us-gaap:CostOfGoodsSoldOilAndGas unitRef="u000" decimals="-5" contextRef="c00005">88100000</us-gaap:CostOfGoodsSoldOilAndGas>
  <!--Cost of natural gas and other products sold (excluding operating expenses shown separately)-->
  <us-gaap:CostOfGoodsSoldOilAndGas unitRef="u000" decimals="-5" contextRef="c00006">226600000</us-gaap:CostOfGoodsSoldOilAndGas>
  <!--Cost of natural gas and other products sold (excluding operating expenses shown separately)-->
  <us-gaap:CostOfGoodsSoldOilAndGas unitRef="u000" decimals="-5" contextRef="c00004">403400000</us-gaap:CostOfGoodsSoldOilAndGas>
  <!--Cost of natural gas and other products sold (excluding operating expenses shown separately)-->
  <us-gaap:CostOfGoodsSoldOilAndGas unitRef="u000" decimals="-5" contextRef="c00002">630600000</us-gaap:CostOfGoodsSoldOilAndGas>
  <!--Total Revenues-->
  <us-gaap:Revenues unitRef="u000" decimals="-5" contextRef="c00005">613100000</us-gaap:Revenues>
  <!--Total Revenues-->
  <us-gaap:Revenues unitRef="u000" decimals="-5" contextRef="c00006">825800000</us-gaap:Revenues>
  <!--Total Revenues-->
  <us-gaap:Revenues unitRef="u000" decimals="-5" contextRef="c00004">1532200000</us-gaap:Revenues>
  <!--Total Revenues-->
  <us-gaap:Revenues unitRef="u000" decimals="-5" contextRef="c00002">1826300000</us-gaap:Revenues>
  <!--Note 4 - Share-Ba...-->
  <us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock contextRef="c00004">Note 4 - Share-Based Compensation
Questar issues stock options and restricted shares to certain officers, employees and non-employee directors under its Long-term Stock Incentive Plan (LTSIP). First half share-based compensation expense amounted to $12.2 million in 2009 compared with $8.5 million in 2008. Deferred share-based compensation, representing the unvested restricted shares awards amounted to $21.3 million at June 30, 2009, and $17.7 million at December 31, 2008. First half cash flow from tax deductions in excess of recognized compensation expense amounted to $1.3 million in 2009 and $12.2 million in 2008. There were 8,200,879 shares available for future grant at June 30, 2009.
The Company uses the Black-Scholes-Merton mathematical model in estimating the fair value of stock options for accounting purposes. Fair-value calculations rely upon subjective assumptions used in the mathematical model and may not be representative of future results. The Black-Scholes-Merton model is intended to measure the value of options traded on an exchange. The calculated fair value of options granted during the six months ended June 30, 2009, and range of major assumptions used in the model at the dates of grant are listed below:
	6 Months Ended
June 30, 2009
	Range of Option Prices
Fair value of options at grant date 	$31.06	$35.38Risk-free interest rate 	2.51%	1.78%Expected price volatility 	29.9%	28.1%Expected dividend yield 	1.61%	1.39%Expected life in years	5.0	5.0
Unvested stock options increased by 957,332 shares in the first half of 2009. Stock-option transactions under the terms of the LTSIP are summarized below:

Outstanding
Options

Price Range	Weighted-
average
PriceBalance at January 1, 2009	4,183,075 	$7.50 - $53.83 	$17.53
Granted	1,004,000 	31.06 -   35.38 	35.01
Exercised	(261,602)	7.50 -   14.01 	8.57 Balance at June 30, 2009	4,925,473 	$7.50 - $53.83 	$21.57


Options Outstanding	Options Exercisable	Unvested Options


Range of exercise
prices
Number outstanding at June 30, 2009	Weighted-average remaining term in years	Weighted-average exercise price	Number exercisable at June 30,2009	Weighted-average exercise price	Number unvested at June 30, 2009	Weighted- average exercise price$  7.50	199,092	0.7	$  7.50	199,092	$ 7.50		11.48  -   11.98 	855,488	2.6	11.58	855,488	11.58		13.56 -   14.86 	1,895,119	2.9	13.71	1,895,119	13.71		17.55 -   31.06 	451,774	3.6	27.57	114,274	23.48	337,500	$28.95
$33.86 - $53.83 	1,524,000	5.7	37.00	46,668	41.08	1,477,332	36.88	4,925,473	3.7	$21.57	3,110,641	$13.50	1,814,832	$35.40
Restricted-share grants typically vest in equal installments over a three or four year period from the grant date. Several grants vest in a single installment after a specified period. The weighted-average vesting period of unvested restricted shares at June 30, 2009, was 19 months. Transactions involving restricted shares under the terms of the LTSIP are summarized below:
	Restricted		Weighted-average
	Shares	Price Range	Price
Balance at January 1, 2009	856,000 	$24.33 - $70.13 	$45.64 Granted	368,700 	31.06  -   36.50 	35.06 Distributed	(305,344)	24.33  -   70.13 	37.34 Forfeited	(1,900)	49.97  -   62.50 	55.91 Balance at June 30, 2009	917,456 	$25.12 - $70.13 	$44.13

Note 4 - Share-Based Compensation

Questar issues stock options and restricted shares to certain officers, employees and non-employee directors under its Long-term Stock Incentive Plan (LTSIP). First half share-based compensation expense amounted to $12.2 million in 2009 compared with $8.5 million in 2008. Deferred share-based compensation, representing the unvested restricted shares awards amounted to $21.3 million at June 30, 2009, and $17.7 million at December 31, 2008. First half cash flow from tax deductions in excess of recognized compensation expense amounted to $1.3 million in 2009 and $12.2 million in 2008. There were 8,200,879 shares available for future grant at June 30, 2009.
The Company uses the Black-Scholes-Merton mathematical model in estimating the fair value of stock options for accounting purposes. Fair-value calculations rely upon subjective assumptions used in the mathematical model and may not be representative of future results. The Black-Scholes-Merton model is intended to measure the value of options traded on an exchange. The calculated fair value of options granted during the six months ended June 30, 2009, and range of major assumptions used in the model at the dates of grant are listed below:
	6 Months Ended
June 30, 2009
	Range of Option Prices
Fair value of options at grant date 	$31.06	$35.38Risk-free interest rate 	2.51%	1.78%Expected price volatility 	29.9%	28.1%Expected dividend yield 	1.61%	1.39%Expected life in years	5.0	5.0
Unvested stock options increased by 957,332 shares in the first half of 2009. Stock-option transactions under the terms of the LTSIP are summarized below:

Outstanding
Options

Price Range	Weighted-
average
PriceBalance at January 1, 2009	4,183,075 	$7.50 - $53.83 	$17.53
Granted	1,004,000 	31.06 -   35.38 	35.01
Exercised	(261,602)	7.50 -   14.01 	8.57 Balance at June 30, 2009	4,925,473 	$7.50 - $53.83 	$21.57


Options Outstanding	Options Exercisable	Unvested Options


Range of exercise
prices
Number outstanding at June 30, 2009	Weighted-average remaining term in years	Weighted-average exercise price	Number exercisable at June 30,2009	Weighted-average exercise price	Number unvested at June 30, 2009	Weighted- average exercise price$  7.50	199,092	0.7	$  7.50	199,092	$ 7.50		11.48  -   11.98 	855,488	2.6	11.58	855,488	11.58		13.56 -   14.86 	1,895,119	2.9	13.71	1,895,119	13.71		17.55 -   31.06 	451,774	3.6	27.57	114,274	23.48	337,500	$28.95
$33.86 - $53.83 	1,524,000	5.7	37.00	46,668	41.08	1,477,332	36.88	4,925,473	3.7	$21.57	3,110,641	$13.50	1,814,832	$35.40
Restricted-share grants typically vest in equal installments over a three or four year period from the grant date. Several grants vest in a single installment after a specified period. The weighted-average vesting period of unvested restricted shares at June 30, 2009, was 19 months. Transactions involving restricted shares under the terms of the LTSIP are summarized below:
	Restricted		Weighted-average
	Shares	Price Range	Price
Balance at January 1, 2009	856,000 	$24.33 - $70.13 	$45.64 Granted	368,700 	31.06  -   36.50 	35.06 Distributed	(305,344)	24.33  -   70.13 	37.34 Forfeited	(1,900)	49.97  -   62.50 	55.91 Balance at June 30, 2009	917,456 	$25.12 - $70.13 	$44.13</us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock>
  <!--Noncontrolling interest-->
  <us-gaap:MinorityInterest unitRef="u000" decimals="-5" contextRef="c00000">55800000</us-gaap:MinorityInterest>
  <!--Noncontrolling interest-->
  <us-gaap:MinorityInterest unitRef="u000" decimals="-5" contextRef="c00003">29500000</us-gaap:MinorityInterest>
  <!--Other noncurrent assets, net-->
  <us-gaap:OtherAssetsNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">37900000</us-gaap:OtherAssetsNoncurrent>
  <!--Other noncurrent assets, net-->
  <us-gaap:OtherAssetsNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">41700000</us-gaap:OtherAssetsNoncurrent>
  <!--Interest and other income-->
  <us-gaap:InvestmentIncomeNonoperating unitRef="u000" decimals="-5" contextRef="c00005">4300000</us-gaap:InvestmentIncomeNonoperating>
  <!--Interest and other income-->
  <us-gaap:InvestmentIncomeNonoperating unitRef="u000" decimals="-5" contextRef="c00006">8300000</us-gaap:InvestmentIncomeNonoperating>
  <!--Interest and other income-->
  <us-gaap:InvestmentIncomeNonoperating unitRef="u000" decimals="-5" contextRef="c00004">8700000</us-gaap:InvestmentIncomeNonoperating>
  <!--Interest and other income-->
  <us-gaap:InvestmentIncomeNonoperating unitRef="u000" decimals="-5" contextRef="c00002">10300000</us-gaap:InvestmentIncomeNonoperating>
  <!--Distribution to noncontrolling interest-->
  <us-gaap:PaymentsOfDividendsMinorityInterest unitRef="u000" decimals="-5" contextRef="c00004">3300000</us-gaap:PaymentsOfDividendsMinorityInterest>
  <!--Distribution to noncontrolling interest-->
  <us-gaap:PaymentsOfDividendsMinorityInterest unitRef="u000" decimals="-5" contextRef="c00002">4800000</us-gaap:PaymentsOfDividendsMinorityInterest>
  <!--Retained earnings-->
  <us-gaap:RetainedEarningsAccumulatedDeficit unitRef="u000" decimals="-5" contextRef="c00000">2873900000</us-gaap:RetainedEarningsAccumulatedDeficit>
  <!--Retained earnings-->
  <us-gaap:RetainedEarningsAccumulatedDeficit unitRef="u000" decimals="-5" contextRef="c00003">2772300000</us-gaap:RetainedEarningsAccumulatedDeficit>
  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeLiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00000">54600000</us-gaap:DerivativeLiabilitiesCurrent>
  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeLiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00003">500000</us-gaap:DerivativeLiabilitiesCurrent>
  <!--Property, Plant and Equipment (successful efforts method for gas and oil properties)-->
  <us-gaap:PropertyPlantAndEquipmentGross unitRef="u000" decimals="-5" contextRef="c00000">10769700000</us-gaap:PropertyPlantAndEquipmentGross>
  <!--Property, Plant and Equipment (successful efforts method for gas and oil properties)-->
  <us-gaap:PropertyPlantAndEquipmentGross unitRef="u000" decimals="-5" contextRef="c00003">10229800000</us-gaap:PropertyPlantAndEquipmentGross>
  <!--Interest expense-->
  <us-gaap:InterestExpense unitRef="u000" decimals="-5" contextRef="c00005">30400000</us-gaap:InterestExpense>
  <!--Interest expense-->
  <us-gaap:InterestExpense unitRef="u000" decimals="-5" contextRef="c00006">32500000</us-gaap:InterestExpense>
  <!--Interest expense-->
  <us-gaap:InterestExpense unitRef="u000" decimals="-5" contextRef="c00004">62200000</us-gaap:InterestExpense>
  <!--Interest expense-->
  <us-gaap:InterestExpense unitRef="u000" decimals="-5" contextRef="c00002">58100000</us-gaap:InterestExpense>
  <!--Cash used in disposition of assets-->
  <us-gaap:PaymentsForProceedsFromRemovalCosts unitRef="u000" decimals="-5" contextRef="c00004">-900000</us-gaap:PaymentsForProceedsFromRemovalCosts>
  <!--Cash used in disposition of assets-->
  <us-gaap:PaymentsForProceedsFromRemovalCosts unitRef="u000" decimals="-5" contextRef="c00002">-3000000</us-gaap:PaymentsForProceedsFromRemovalCosts>
  <!--Net (gain) from asset sales-->
  <us-gaap:GainLossOnSaleOfPropertyPlantEquipment unitRef="u000" decimals="-5" contextRef="c00004">-1700000</us-gaap:GainLossOnSaleOfPropertyPlantEquipment>
  <!--Net (gain) from asset sales-->
  <us-gaap:GainLossOnSaleOfPropertyPlantEquipment unitRef="u000" decimals="-5" contextRef="c00002">-3400000</us-gaap:GainLossOnSaleOfPropertyPlantEquipment>
  <!--Pension and postretirement benefits-->
  <us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">252900000</us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent>
  <!--Pension and postretirement benefits-->
  <us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">250000000</us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent>
  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeAssetsNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">45900000</us-gaap:DerivativeAssetsNoncurrent>
  <!--Fair value of derivative contracts-->
  <us-gaap:DerivativeAssetsNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">106300000</us-gaap:DerivativeAssetsNoncurrent>
  <!--NET INCOME ATTRIBUTABLE TO QUESTAR-->
  <us-gaap:NetIncomeLoss unitRef="u000" decimals="-5" contextRef="c00005">77900000</us-gaap:NetIncomeLoss>
  <!--NET INCOME ATTRIBUTABLE TO QUESTAR-->
  <us-gaap:NetIncomeLoss unitRef="u000" decimals="-5" contextRef="c00006">172600000</us-gaap:NetIncomeLoss>
  <!--NET INCOME ATTRIBUTABLE TO QUESTAR-->
  <us-gaap:NetIncomeLoss unitRef="u000" decimals="-5" contextRef="c00004">145100000</us-gaap:NetIncomeLoss>
  <!--NET INCOME ATTRIBUTABLE TO QUESTAR-->
  <us-gaap:NetIncomeLoss unitRef="u000" decimals="-5" contextRef="c00002">358400000</us-gaap:NetIncomeLoss>
  <!--INCOME BEFORE INCOME TAXES-->
  <us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00005">123000000</us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments>
  <!--INCOME BEFORE INCOME TAXES-->
  <us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00006">276900000</us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments>
  <!--INCOME BEFORE INCOME TAXES-->
  <us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00004">229400000</us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments>
  <!--INCOME BEFORE INCOME TAXES-->
  <us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00002">575800000</us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments>
  <!--Income from unconsolidated affiliates-->
  <us-gaap:IncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00005">1400000</us-gaap:IncomeLossFromEquityMethodInvestments>
  <!--Income from unconsolidated affiliates-->
  <us-gaap:IncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00006">200000</us-gaap:IncomeLossFromEquityMethodInvestments>
  <!--Income from unconsolidated affiliates-->
  <us-gaap:IncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00004">3000000</us-gaap:IncomeLossFromEquityMethodInvestments>
  <!--Income from unconsolidated affiliates-->
  <us-gaap:IncomeLossFromEquityMethodInvestments unitRef="u000" decimals="-5" contextRef="c00002">400000</us-gaap:IncomeLossFromEquityMethodInvestments>
  <!--Operating and maintenance-->
  <us-gaap:CostOfPropertyRepairsAndMaintenance unitRef="u000" decimals="-5" contextRef="c00005">84200000</us-gaap:CostOfPropertyRepairsAndMaintenance>
  <!--Operating and maintenance-->
  <us-gaap:CostOfPropertyRepairsAndMaintenance unitRef="u000" decimals="-5" contextRef="c00006">90600000</us-gaap:CostOfPropertyRepairsAndMaintenance>
  <!--Operating and maintenance-->
  <us-gaap:CostOfPropertyRepairsAndMaintenance unitRef="u000" decimals="-5" contextRef="c00004">184500000</us-gaap:CostOfPropertyRepairsAndMaintenance>
  <!--Operating and maintenance-->
  <us-gaap:CostOfPropertyRepairsAndMaintenance unitRef="u000" decimals="-5" contextRef="c00002">178500000</us-gaap:CostOfPropertyRepairsAndMaintenance>
  <!--Note 9 - Employee...-->
  <us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock contextRef="c00004">Note 9 - Employee Benefits	Questar has defined-benefit pension and postretirement medical and life insurance plans covering the majority of its employees. Questar is subject to and complies with minimum-required and maximum-allowed annual contribution levels for its qualified retirement plan as determined by the Employee Retirement Income Security Act and Internal Revenue Code. Subject to these limitations, Questar plans to fund the qualified retirement plan in amounts approximately equal to the yearly expense, which is estimated to be $18.4 million for 2009. Pension expense increased year-over-year because returns on plan assets were lower than expected.
The Company also has a nonqualified pension plan for eligible employees, which provides a benefit in addition to the benefit limit defined by the Internal Revenue Service for qualified pension plans. The nonqualified pension plan is unfunded. Claims are paid from the Company general funds. The 2009 expense is estimated to be $3.2 million.
Components of the qualified and nonqualified pension expense included in the determination of net income are listed below:
	3 Months Ended June 30,	6 Months Ended June 30,	2009	2008	2009	2008	(in millions)Service cost	$2.5 	$ 2.4 	$5.0 	$ 4.8 Interest cost	7.1 	6.6 	14.3 	13.2 Expected return on plan assets	(6.3)	(6.8)	(12.7)	(13.6)Prior service and other costs	0.3 	0.3 	0.6 	0.6 Recognized net-actuarial loss	1.4 	0.8 	2.9 	1.6 Settlement costs	0.3 		0.6 	  Pension expense	$5.3 	$ 3.3 	$10.7 	$ 6.6
The Company currently estimates a $6.3 million expense for postretirement benefits other than pensions in 2009 before $0.8 million for accretion of a regulatory liability. Expense components are listed below:
	3 Months Ended June 30,	6 Months Ended June 30,
	2009	2008	2009	2008	(in millions)Service cost	$0.2 	$ 0.2 	$0.4 	$ 0.4 Interest cost	1.2 	1.2 	2.4 	2.4 Expected return on plan assets	(0.6)	(0.9)	(1.1)	(1.7)Amortization of transition obligation	0.4 	0.5 	0.9 	0.9 Amortization of losses	0.2 		0.5 	Accretion of regulatory liability	0.2 	0.2 	0.4 	0.4   Postretirement benefits expense	$1.6 	$ 1.2 	$3.5 	$ 2.4</us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock>
  <!--Total Assets-->
  <us-gaap:Assets unitRef="u000" decimals="-5" contextRef="c00000">8404500000</us-gaap:Assets>
  <!--Total Assets-->
  <us-gaap:Assets unitRef="u000" decimals="-5" contextRef="c00003">8630700000</us-gaap:Assets>
  <!--NET INCOME-->
  <us-gaap:ProfitLoss unitRef="u000" decimals="-5" contextRef="c00005">78500000</us-gaap:ProfitLoss>
  <!--NET INCOME-->
  <us-gaap:ProfitLoss unitRef="u000" decimals="-5" contextRef="c00006">174700000</us-gaap:ProfitLoss>
  <!--NET INCOME-->
  <us-gaap:ProfitLoss unitRef="u000" decimals="-5" contextRef="c00004">146200000</us-gaap:ProfitLoss>
  <!--NET INCOME-->
  <us-gaap:ProfitLoss unitRef="u000" decimals="-5" contextRef="c00002">362900000</us-gaap:ProfitLoss>
  <!--Questar Pipeline-->
  <us-gaap:GasDomesticRegulatedRevenue unitRef="u000" decimals="-5" contextRef="c00005">43000000</us-gaap:GasDomesticRegulatedRevenue>
  <!--Questar Pipeline-->
  <us-gaap:GasDomesticRegulatedRevenue unitRef="u000" decimals="-5" contextRef="c00006">43300000</us-gaap:GasDomesticRegulatedRevenue>
  <!--Questar Pipeline-->
  <us-gaap:GasDomesticRegulatedRevenue unitRef="u000" decimals="-5" contextRef="c00004">83700000</us-gaap:GasDomesticRegulatedRevenue>
  <!--Questar Pipeline-->
  <us-gaap:GasDomesticRegulatedRevenue unitRef="u000" decimals="-5" contextRef="c00002">88000000</us-gaap:GasDomesticRegulatedRevenue>
  <!--Market Resources-->
  <us-gaap:OilAndGasRevenue unitRef="u000" decimals="-5" contextRef="c00005">431600000</us-gaap:OilAndGasRevenue>
  <!--Market Resources-->
  <us-gaap:OilAndGasRevenue unitRef="u000" decimals="-5" contextRef="c00006">623000000</us-gaap:OilAndGasRevenue>
  <!--Market Resources-->
  <us-gaap:OilAndGasRevenue unitRef="u000" decimals="-5" contextRef="c00004">904300000</us-gaap:OilAndGasRevenue>
  <!--Market Resources-->
  <us-gaap:OilAndGasRevenue unitRef="u000" decimals="-5" contextRef="c00002">1188600000</us-gaap:OilAndGasRevenue>
  <!--Total capital expenditures-->
  <us-gaap:PaymentsToAcquireProductiveAssets unitRef="u000" decimals="-5" contextRef="c00004">-703100000</us-gaap:PaymentsToAcquireProductiveAssets>
  <!--Total capital expenditures-->
  <us-gaap:PaymentsToAcquireProductiveAssets unitRef="u000" decimals="-5" contextRef="c00002">-1412300000</us-gaap:PaymentsToAcquireProductiveAssets>
  <!--Depreciation, depletion and amortization-->
  <us-gaap:DepreciationDepletionAndAmortization unitRef="u000" decimals="-5" contextRef="c00004">345500000</us-gaap:DepreciationDepletionAndAmortization>
  <!--Depreciation, depletion and amortization-->
  <us-gaap:DepreciationDepletionAndAmortization unitRef="u000" decimals="-5" contextRef="c00002">229700000</us-gaap:DepreciationDepletionAndAmortization>
  <!--Total Liabilities and Equity-->
  <us-gaap:LiabilitiesAndStockholdersEquity unitRef="u000" decimals="-5" contextRef="c00000">8404500000</us-gaap:LiabilitiesAndStockholdersEquity>
  <!--Total Liabilities and Equity-->
  <us-gaap:LiabilitiesAndStockholdersEquity unitRef="u000" decimals="-5" contextRef="c00003">8630700000</us-gaap:LiabilitiesAndStockholdersEquity>
  <!--Accumulated depreciation, depletion and amortization-->
  <us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment unitRef="u000" decimals="-5" contextRef="c00000">3420200000</us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment>
  <!--Accumulated depreciation, depletion and amortization-->
  <us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment unitRef="u000" decimals="-5" contextRef="c00003">3096800000</us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment>
  <!--Production and other taxes-->
  <us-gaap:TaxesOther unitRef="u000" decimals="-5" contextRef="c00005">24900000</us-gaap:TaxesOther>
  <!--Production and other taxes-->
  <us-gaap:TaxesOther unitRef="u000" decimals="-5" contextRef="c00006">49300000</us-gaap:TaxesOther>
  <!--Production and other taxes-->
  <us-gaap:TaxesOther unitRef="u000" decimals="-5" contextRef="c00004">53900000</us-gaap:TaxesOther>
  <!--Production and other taxes-->
  <us-gaap:TaxesOther unitRef="u000" decimals="-5" contextRef="c00002">90100000</us-gaap:TaxesOther>
  <!--Entity Common Stock, Shares Outstanding-->
  <dei:EntityCommonStockSharesOutstanding unitRef="u001" decimals="0" contextRef="c00008">174227789</dei:EntityCommonStockSharesOutstanding>
  <!--Entity Filer Category-->
  <dei:EntityFilerCategory contextRef="c00004">Large Accelerated Filer</dei:EntityFilerCategory>
  <!--Accumulated other comprehensive income-->
  <us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax unitRef="u000" decimals="-5" contextRef="c00000">106700000</us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax>
  <!--Accumulated other comprehensive income-->
  <us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax unitRef="u000" decimals="-5" contextRef="c00003">194700000</us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax>
  <!--Deferred income taxes-->
  <us-gaap:DeferredTaxLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00000">1364700000</us-gaap:DeferredTaxLiabilitiesNoncurrent>
  <!--Deferred income taxes-->
  <us-gaap:DeferredTaxLiabilitiesNoncurrent unitRef="u000" decimals="-5" contextRef="c00003">1334100000</us-gaap:DeferredTaxLiabilitiesNoncurrent>
  <!--Total Current Liabilities-->
  <us-gaap:LiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00000">713900000</us-gaap:LiabilitiesCurrent>
  <!--Total Current Liabilities-->
  <us-gaap:LiabilitiesCurrent unitRef="u000" decimals="-5" contextRef="c00003">1132900000</us-gaap:LiabilitiesCurrent>
  <!--Income taxes-->
  <us-gaap:IncomeTaxExpenseBenefit unitRef="u000" decimals="-5" contextRef="c00005">44500000</us-gaap:IncomeTaxExpenseBenefit>
  <!--Income taxes-->
  <us-gaap:IncomeTaxExpenseBenefit unitRef="u000" decimals="-5" contextRef="c00006">102200000</us-gaap:IncomeTaxExpenseBenefit>
  <!--Income taxes-->
  <us-gaap:IncomeTaxExpenseBenefit unitRef="u000" decimals="-5" contextRef="c00004">83200000</us-gaap:IncomeTaxExpenseBenefit>
  <!--Income taxes-->
  <us-gaap:IncomeTaxExpenseBenefit unitRef="u000" decimals="-5" contextRef="c00002">212900000</us-gaap:IncomeTaxExpenseBenefit>

</xbrl>

