Risk Management and Trading Activities (Details 3) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Changes in financial assets and liabilities at fair value based on level 3 inputs
Balance at beginning of period	$ 787	$ (46)	$ 412	$ 84
Unrealized gains (losses)
Included in earnings	(208)	(45)	104	58
Included in other comprehensive income	7	94	17	80
Purchases	702	343	1,517	435
Sales	(776)	(245)	(1,595)	(348)
Settlements	(52)	(14)	(32)	(45)
Transfers into Level 3	(72)	1	11	(158)
Transfers out of Level 3	(16)	(47)	(62)	(65)
Balance at end of period	$ 372	$ 41	$ 372	$ 41

Purchases that have taken place during the period in relation to net assets/liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

Name:	hes_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetLiabilitiesPurchases
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sales that have taken place during the period in relation to net assets/liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ Details

Name:	hes_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetLiabilitiesSales
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Settlements that have taken place during the period in relation to net assets/liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ Details

Name:	hes_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetLiabilitiesSettlements
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Financial assets and liabilities measured at fair value based on level 3 inputs.

+ Details

Name:	hes_FinancialAssetsAndLiabilitiesMeasuredAtFairValue
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents (net) transfers into assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

+ Details

Name:	hes_TransfersIntoLevelThree
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents (net) transfers out of assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

+ Details

Name:	hes_TransfersOutOfLevelThree
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings.

+ Details

Name:	hes_UnrealizedGainsLossesIncludedInEarnings
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

+ Details

Name:	hes_UnrealizedGainsLossesIncludedInOtherComprehensiveIncome
Namespace Prefix:	hes
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration