|
Balance Sheet Amounts Associated With Medicare Part D (Detail) (USD $)
In Millions, unless otherwise specified |
Jun. 30, 2012
|
Dec. 31, 2011
|
|---|---|---|
| Segment Reporting Information [Line Items] | ||
| Other current assets | $ 1,422 | $ 1,027 |
| Trade accounts payable and accrued expenses | (2,081) | (1,783) |
| Other long-term assets | 1,233 | 1,165 |
| Other long-term liabilities | (321) | (267) |
|
Risk Corridor Settlement
|
||
| Segment Reporting Information [Line Items] | ||
| Other current assets | 37 | 2 |
| Trade accounts payable and accrued expenses | (328) | (331) |
| Net current (liability) asset | (291) | (329) |
| Other long-term assets | 8 | 0 |
| Other long-term liabilities | (50) | 0 |
| Net long-term liability | (42) | 0 |
| Total net (liability) asset | (333) | (329) |
|
CMS Subsidies
|
||
| Segment Reporting Information [Line Items] | ||
| Other current assets | 437 | 363 |
| Trade accounts payable and accrued expenses | (428) | (139) |
| Net current (liability) asset | 9 | 224 |
| Other long-term assets | 0 | 0 |
| Other long-term liabilities | 0 | 0 |
| Net long-term liability | 0 | 0 |
| Total net (liability) asset | $ 9 | $ 224 |