| Fair Value of Derivatives by Level of Inputs [Table Text Block] |
The following tables summarize information regarding marketable securities (dollars in millions): | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | June 30, 2012 | | | | Unrealized | | Fair Value | | Fair Value Measurements on a Recurring Basis | | Cost | | Gains | | Losses | | | Level 1 | | Level 2 | | Level 3 | Cash and cash equivalents | | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | U.S. government and agencies | $ | 8,042 |
| | $ | — |
| | $ | — |
| | $ | 8,042 |
| | $ | — |
| | $ | 8,042 |
| | $ | — |
| Sovereign debt | 441 |
| | — |
| | — |
| | 441 |
| | — |
| | 441 |
| | — |
| Certificates of deposit | 350 |
| | — |
| | — |
| | 350 |
| | — |
| | 350 |
| | — |
| Money market funds | 1,309 |
| | — |
| | — |
| | 1,309 |
| | 1,309 |
| | — |
| | — |
| Corporate debt | 4,794 |
| | — |
| | — |
| | 4,794 |
| | — |
| | 4,794 |
| | — |
| Total marketable securities classified as cash equivalents | $ | 14,936 |
| | $ | — |
| | $ | — |
| | 14,936 |
| | $ | 1,309 |
| | $ | 13,627 |
| | $ | — |
| Cash, time deposits, and other cash equivalents | | | | | | | 7,248 |
| | | | | | | Total cash and cash equivalents | | | | | | | $ | 22,184 |
| | | | | | | Marketable securities - current | | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | U.S. government and agencies | $ | 1,370 |
| | $ | — |
| | $ | — |
| | $ | 1,370 |
| | $ | — |
| | $ | 1,370 |
| | $ | — |
| Sovereign debt | 67 |
| | — |
| | — |
| | 67 |
| | — |
| | 67 |
| | — |
| Certificates of deposit | 40 |
| | — |
| | — |
| | 40 |
| | — |
| | 40 |
| | — |
| Corporate debt | 3,479 |
| | 4 |
| | 2 |
| | 3,481 |
| | — |
| | 3,481 |
| | — |
| Total available-for-sale securities | $ | 4,956 |
| | $ | 4 |
| | $ | 2 |
| | 4,958 |
| | — |
| | 4,958 |
| | — |
| Trading securities(a) | | | | | | | | | | | | | | Sovereign debt | | | | | | | 6,423 |
| | — |
| | 6,423 |
| | — |
| Total trading securities | | | | | | | 6,423 |
| | — |
| | 6,423 |
| | — |
| Total marketable securities - current | | | | | | | 11,381 |
| | — |
| | 11,381 |
| | — |
| Marketable securities - non-current | | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | Equity(b) | $ | 404 |
| | $ | — |
| | $ | 160 |
| | 244 |
| | 244 |
| | — |
| | — |
| Total marketable securities - non-current | $ | 404 |
| | $ | — |
| | $ | 160 |
| | 244 |
| | 244 |
| | — |
| | — |
| Total marketable securities | | | | | | | $ | 11,625 |
| | $ | 244 |
| | $ | 11,381 |
| | $ | — |
| Restricted cash and marketable securities | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | Money market funds | $ | 1,027 |
| | $ | — |
| | $ | — |
| | $ | 1,027 |
| | $ | 1,027 |
| | $ | — |
| | $ | — |
| Sovereign debt | 20 |
| | — |
| | — |
| | 20 |
| | — |
| | 20 |
| | — |
| Other | 169 |
| | — |
| | — |
| | 169 |
| | — |
| | 169 |
| | — |
| Total marketable securities classified as restricted cash and marketable securities | $ | 1,216 |
| | $ | — |
| | $ | — |
| | 1,216 |
| | $ | 1,027 |
| | $ | 189 |
| | $ | — |
| Restricted cash, time deposits, and other restricted cash equivalents | | | | | | | 564 |
| | | | | | | Total restricted cash and marketable securities | | | | | | | $ | 1,780 |
| | | | | | |
________ | | (a) | Net unrealized losses on trading securities were $111 million and $61 million in the three and six months ended June 30, 2012. Net unrealized gains (losses) were insignificant in the three and six months ended June 30, 2011. Unrealized gains (losses) are primarily related to remeasurement of Canadian Dollar (CAD) denominated securities. |
| | (b) | Represents our seven percent ownership in PSA acquired in connection with our agreement with PSA to create a long-term and strategic alliance. The investment is recorded in Other assets and deferred income taxes. |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | December 31, 2011 | | | | Unrealized | | Fair Value | | Fair Value Measurements on a Recurring Basis | | Cost | | Gains | | Losses | | | Level 1 | | Level 2 | | Level 3 | Cash and cash equivalents | | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | U.S. government and agencies | $ | 239 |
| | $ | — |
| | $ | — |
| | $ | 239 |
| | $ | — |
| | $ | 239 |
| | $ | — |
| Sovereign debt | 490 |
| | — |
| | — |
| | 490 |
| | — |
| | 490 |
| | — |
| Certificates of deposit | 2,028 |
| | — |
| | — |
| | 2,028 |
| | — |
| | 2,028 |
| | — |
| Money market funds | 1,794 |
| | — |
| | — |
| | 1,794 |
| | 1,794 |
| | — |
| | — |
| Corporate debt | 5,112 |
| | — |
| | — |
| | 5,112 |
| | — |
| | 5,112 |
| | — |
| Total available-for-sale securities | $ | 9,663 |
| | $ | — |
| | $ | — |
| | 9,663 |
| | 1,794 |
| | 7,869 |
| | — |
| Trading securities | | | | | | | | | | | | | | Sovereign debt | | | | | | | 497 |
| | — |
| | 497 |
| | — |
| Total trading securities | | | | | | | 497 |
| | — |
| | 497 |
| | — |
| Total marketable securities classified as cash equivalents | | | | | | | 10,160 |
| | $ | 1,794 |
| | $ | 8,366 |
| | $ | — |
| Cash, time deposits, and other cash equivalents | | | | | | | 5,911 |
| | | | | | | Total cash and cash equivalents | | | | | | | $ | 16,071 |
| | | | | | | Marketable securities - current | | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | U.S. government and agencies | $ | 5,214 |
| | $ | 2 |
| | $ | — |
| | $ | 5,216 |
| | $ | — |
| | $ | 5,216 |
| | $ | — |
| Sovereign debt | 143 |
| | — |
| | — |
| | 143 |
| | — |
| | 143 |
| | — |
| Certificates of deposit | 178 |
| | — |
| | — |
| | 178 |
| | — |
| | 178 |
| | — |
| Corporate debt | 4,566 |
| | 3 |
| | 4 |
| | 4,565 |
| | — |
| | 4,565 |
| | — |
| Total available-for-sale securities | $ | 10,101 |
| | $ | 5 |
| | $ | 4 |
| | 10,102 |
| | — |
| | 10,102 |
| | — |
| Trading securities | | | | | | | | | | | | | | Equity | | | | | | | 34 |
| | 34 |
| | — |
| | — |
| Sovereign debt | | | | | | | 5,936 |
| | — |
| | 5,936 |
| | — |
| Other debt | | | | | | | 76 |
| | — |
| | 76 |
| | — |
| Total trading securities | | | | | | | 6,046 |
| | 34 |
| | 6,012 |
| | — |
| Total marketable securities - current | | | | | | | $ | 16,148 |
| | $ | 34 |
| | $ | 16,114 |
| | $ | — |
| Restricted cash and marketable securities | | | | | | | | | | | | | Available-for-sale securities | | | | | | | | | | | | | | Money market funds | $ | 1,363 |
| | $ | — |
| | $ | — |
| | $ | 1,363 |
| | $ | 1,363 |
| | $ | — |
| | $ | — |
| Sovereign debt | 15 |
| | — |
| | — |
| | 15 |
| | — |
| | 15 |
| | — |
| Other | 161 |
| | 3 |
| | — |
| | 164 |
| | — |
| | 164 |
| | — |
| Total marketable securities classified as restricted cash and marketable securities | $ | 1,539 |
| | $ | 3 |
| | $ | — |
| | 1,542 |
| | $ | 1,363 |
| | $ | 179 |
| | $ | — |
| Restricted cash, time deposits, and other restricted cash equivalents
| | | | | | | 691 |
| | | | | | | Total restricted cash and marketable securities | | | | | | | $ | 2,233 |
| | | | | | |
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