Reportable Segments - Additional Information (Detail)	6 Months Ended
Jun. 30, 2012 Segment	Jun. 30, 2011
Segment Reporting Disclosure [Line Items]
Number of reportable segments	2
Major customers description	All revenues are from external customers and there is no customer who contributed 10% or more of the Company's total revenues during the six months ended June 30, 2012 and 2011.	All revenues are from external customers and there is no customer who contributed 10% or more of the Company's total revenues during the six months ended June 30, 2012 and 2011.

Disclosure of the extent of enterprise reliance on its major customers. For example, includes revenues from transactions with a single external customer amounting to 10 percent or more of the entity's revenues, the total amount of revenues from each such customer, and the identity of the segment or segments reporting the revenues. A group of entities that the entity knows to be under common control generally will be considered a single customer for inclusion in this item. The federal government, a state government, a local government (for example, a county or municipality), or a foreign government each will generally be considered as a single customer for inclusion in this item.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 39

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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