Property, Plant and Equipment (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2012 Room sqft Suite	Sep. 30, 2012	Sep. 30, 2012	May 31, 2012 Offshore Drilling Equipment [Member]
Property, Plant and Equipment [Line Items]
Non-cash ceiling test impairment charges		$ 261	$ 527
Non-cash ceiling test impairment charges after tax		166	336
Non-cash ceiling test impairment charge excluding impact of cash flow hedges		322	657
Non-cash ceiling test impairment charge excluding impact of cash flow hedges, after tax		205	419
Impairment charges			0
Construction in process of new ultra-deepwater drillship				169
Total cost including commissioning, spares and project management				655
Proceeds from sale of rigs	132
Pre-tax gain on sale of rigs	$ 76
Number of guestrooms	630
Number of suites	32
Number of square feet	48,000