v2.4.0.6

Cash Flow Information - Cash Flow Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Noncash Investing and Financing Activities
Increase in PP&E related to an increase in asset retirement obligations	$ 182	$ 808	$ 974
Cash Payments
Interest	919	1,120	1,052
Income taxes	10,285	8,262	6,377
Net Sales (Purchases) of Short-Term Investments
Short-term investments purchased	(6,744)	(982)
Short-term investments sold	7,144
Net Purchases Of Short Term Investment, Total	$ 400	$ (982)

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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