Commitments and Contingencies (Environmental) (Details)	1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) Superfund_Sites	Dec. 31, 2015 USD ($) Superfund_Sites	Dec. 31, 2014 USD ($) number_of_paymentinstallments	Apr. 22, 2010 USD ($) Fatalities
Site Contingency [Line Items]
BP Fault Apportionment in Macondo Ruling				67.00%
Transocean Fault Apportionment In Macondo Ruling				30.00%
Halliburton Fault Apportionment In Macondo Ruling				3.00%
Installment Payment for Legal Fees | number_of_paymentinstallments				1
Loss Contingency Accrual, Payments	$ 1,100,000,000	$ 333,000,000
Number of Payment Installments | number_of_paymentinstallments				3
Number Of Years	2 years
Loss Contingency, Accrual, Current		400,000,000	$ 400,000,000	$ 367,000,000
Loss Contingency, Accrual, Noncurrent		72,000,000	72,000,000
Accrual for Environmental Loss Contingencies Disclosure [Abstract]
Accrued liabilities for environmental matters		$ 50,000,000	$ 50,000,000	$ 57,000,000
Superfund Sites [Member]
Accrual for Environmental Loss Contingencies Disclosure [Abstract]
Number of superfund sites | Superfund_Sites		8	8
Accrual for site contingency		$ 3,000,000	$ 3,000,000
Damage from Fire, Explosion or Other Hazard [Member]
Site Contingency [Line Items]
Number Of Fatalities | Fatalities					11
Maximum Per Day Fine For Violating Federal Regulations Related To Incs		35,000
Loss Contingency Accrual		472,000,000	472,000,000
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