Commitments and Contingencies (Details)	1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) Class_Actions	Dec. 31, 2015 USD ($) Class_Actions	Dec. 31, 2014 USD ($) number_of_paymentinstallments	Apr. 22, 2010 USD ($) Fatalities
Loss Contingencies [Line Items]
Loss Contingency, Accrual, Current		$ 400,000,000	$ 400,000,000	$ 367,000,000
Loss Contingency, Accrual, Noncurrent		72,000,000	72,000,000
Litigation [Abstract]
Loss Contingency Accrual, Payments	$ 1,100,000,000	333,000,000
Number of Payment Installments | number_of_paymentinstallments				3
Number Of Years	2 years
Installment Payment for Legal Fees | number_of_paymentinstallments				1
BP Fault Apportionment in Macondo Ruling				67.00%
Transocean Fault Apportionment In Macondo Ruling				30.00%
Halliburton Fault Apportionment In Macondo Ruling				3.00%
Indemnification and insurance [Abstract]
Insurance coverage not reimbursed		200,000,000	200,000,000
Estimated Recovery from Third Party		118,000,000	118,000,000
Macondo well incident
Loss Contingencies [Line Items]
Number of fatalities | Fatalities					11
Maximum per day fine for violating federal regulations related to INCs		35,000
Litigation [Abstract]
Loss Contingency Accrual		472,000,000	472,000,000
Indemnification and insurance [Abstract]
Total amount of general liability insurance program					$ 600,000,000
Legal fees			1,500,000,000
General Liability Insurance Program Covered Expenses		$ 403,000,000	$ 403,000,000
Securities and related litigation
Litigation [Abstract]
Number of similar class action lawsuits that were later consolidated into one suit | Class_Actions		20	20