Property and Equipment - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Property, Plant and Equipment [Line Items]
Capital expenditures	$ 1,700,000,000	$ 1,700,000,000	$ 1,700,000,000	$ 1,700,000,000
Capitalized interest on construction-in-progress	11,000,000	31,000,000	39,000,000	92,000,000
Paragon Offshore [Member] | Spinoff [Member]
Property, Plant and Equipment [Line Items]
Capital expenditures	$ 15,000,000		$ 150,000,000