Summary of Significant Accounting Policies (Summary of Conversion Rates) (Detail)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Jan. 31, 2008
Significant Accounting Policies [Line Items]
Year end RMB: U.S. Dollar exchange rate	6.2666	6.3011	6.3247	7.3141
Average RMB: U.S. Dollar exchange rate	6.2769	6.3034	6.3201

Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 30

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

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