Variable Interest Entities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2014 USD ($) item	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Unconsolidated Variable interest entities
Number of Midwater Floaters sold (in drilling units) | item	2
Cash proceeds from repayment of notes receivable	$ 98
Gain associated with the prepayment of notes receivable	$ 7
ADDCL
Carrying amounts associated with consolidated variable interest entities
Assets		$ 787	$ 849
Liabilities		25	46
Net carrying amount		$ 762	803
TDSOI
Carrying amounts associated with consolidated variable interest entities
Assets			298
Liabilities			3
Net carrying amount			$ 295