Debt (Combined Schedule of Current and Noncurrent Debt and Capital Lease Obligations) (Details) (USD $) In Millions	6 Months Ended
	Jun. 30, 2011
Debt maturing within one year, beginning	$ 7,542
Long-term debt and capital lease obligations - beginning balance	45,252
Total, beginning balance	52,794
Proceeds from long-term borrowings	6,440
Repayments of long-term borrowings and capital leases obligations	(7,356)
Increase in short-term obligations, excluding current maturities	1,012
Debt acquired	748
Other	344
Debt maturing within one year, ending	6,055
Long-term debt, ending	47,927
Total, ending balance	53,982
Long-term Debt [Member]
Long-term debt and capital lease obligations - beginning balance	45,252
Proceeds from long-term borrowings	6,440
Reclassifications of long-term debt	(3,850)
Other	85
Long-term debt, ending	47,927
Debt Maturing Within One Year [Member]
Debt maturing within one year, beginning	7,542
Repayments of long-term borrowings and capital leases obligations	(7,356)
Increase in short-term obligations, excluding current maturities	1,012
Reclassifications of long-term debt	3,850
Debt acquired	748
Other	259
Debt maturing within one year, ending	$ 6,055