|
Lease Commitments Narrative (Detail) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2011
|
Dec. 31, 2010
|
Dec. 31, 2009
|
|
| Operating Leased Assets [Line Items] | |||
| Rental expense, net of sublease income | $ 382 | $ 387 | $ 356 |