Long-Lived Assets by Geographic Area (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Long-lived assets:
Long-lived assets	$ 32,194	$ 19,816
United States
Long-lived assets:
Long-lived assets	19,265	15,963
International
Long-lived assets:
Long-lived assets	$ 12,929	$ 3,853