Retirement Plans - Amounts Recognized in Consolidated Balance Sheet (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Compensation And Retirement Disclosure [Abstract]
After-tax deficit reflected in Accumulated other comprehensive income (loss)	$ 652	$ 342

After-tax reduction to equity recorded in Accumulated other comprehensive income (loss).

No definition available.

Name:	hes_AfterTaxReductionToEquityRecordedInAccumulatedOtherComprehensiveIncomeLoss
Namespace Prefix:	hes_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant