Market Concentration and Risks - Summary of Carrying Amounts of Net Assets Belonging to International Operations (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Canada & Latin America [Member]
Concentration Risk [Line Items]
Carrying amounts of net assets belonging to international operations	$ 131,974	$ 47,274
Europe, Africa & Middle East [Member]
Concentration Risk [Line Items]
Carrying amounts of net assets belonging to international operations	43,286	51,050
Asia Pacific [Member]
Concentration Risk [Line Items]
Carrying amounts of net assets belonging to international operations	$ 205,424	$ 221,040

Carrying amount of total assets less total liabilities of a designated geographic area if disclosed as a concentration risk.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 94-6

-Paragraph 24

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant