Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Loss Contingency [Abstract]
Reserves for potential fines for competition law violations	$ 335

The carrying amount as of the balance sheet date of the combined total of loss contingency reserves.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

Name:	us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant