Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015
Commitments [Line Items]
Aggregate amount related to indemnification agreements	$ 324,000,000
Aggregate amount related to quantifiable guarantees	375,000,000
Potential amount of future payments under guarantees	2,000,000,000
Harsh Environment Semisubmersible Drilling Rig [Member]
Commitments [Line Items]
Total cost of the project	764,000,000
Remaining contractual payment is due upon delivery of rig	440,000,000
Ultra-deepwater Drillships [Member]
Commitments [Line Items]
Remaining contractual payment is due upon delivery of rig	$ 395,000,000