Accounts, Notes and Other Receivables (Details) (USD $) In Millions | Sep. 30, 2011 | Dec. 31, 2010 |
|---|---|---|
| Accounts Receivable Net Current [Abstract] | ||
| Trade | $ 7,101 | $ 6,471 |
| Other Accounts Receivable | 455 | 647 |
| Accounts, Notes, and Other Recivables, Gross | 7,556 | 7,118 |
| Less - Allowance for doubtful accounts | (240) | (277) |
| Accounts, Notes and Other Receivables, Net | 7,316 | 6,841 |
| Accounts Notes And Other Receivables Paragraph Details [Abstract] | ||
| Unbilled Contracts Receivable | $ 1,495 | $ 1,307 |