Commitments and Contingencies (Details)	1 Months Ended	3 Months Ended
	Sep. 30, 2014 USD ($)	Mar. 31, 2016 USD ($) Class_Actions	Dec. 31, 2015 USD ($) number_of_paymentinstallments	Apr. 22, 2010 USD ($) Fatalities
Loss Contingencies [Line Items]
Liabilities for Macondo well incident		$ 400,000,000	$ 400,000,000
Loss Contingency, Information about Litigation Matters [Abstract]
Loss Contingency, Settlement Agreement, Terms	$ 1,100,000,000
Number of Payment Installments | number_of_paymentinstallments			3
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%
Number Of Years	2 years
Macondo well incident
Loss Contingencies [Line Items]
Loss contingency related to Macondo well incident (non-current)		72,000,000
Loss contingency related to Macondo well (total)		472,000,000
Loss Contingency, Estimated Recovery from Third Party		100,000,000
Liabilities for Macondo well incident		400,000,000
Number of fatalities | Fatalities				11
Maximum per day fine for violating federal regulations related to INCs		35,000
Indemnification and insurance [Abstract]
Total amount of general liability insurance program				$ 600,000,000
Legal Fees		1,500,000,000
Legal fees and related expenses covered by insurance		$ 409,000,000
Securities and related litigation
Loss Contingency, Information about Litigation Matters [Abstract]
Number of similar class action lawsuits that were later consolidated into one suit | Class_Actions		20