Restricted Net Assets (Details) (USD $)	3 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Restricted Net Assets (Textual)
Annual appropriations required by statutory reserve fund	At least 10% of after-tax profit, if any, of the relevant PRC VIE's and subsidiary.
Company's restricted net assets	$ 79,734,000	$ 77,514,000

Total assets that cannot be used for operating purposes because of contract or regulatory requirements that are in effect for a period that extends beyond one year.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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