Disposal of a Subsidiary (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended	1 Months Ended	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Jan. 31, 2012 Shanghai Yiyi [Member]	Dec. 31, 2012 Shanghai Yiyi [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of disposed equity interest			53.50%
Cash consideration of equity interest disposed			$ 4,207
Gain on disposal of a subsidiary	$ 3,566	$ 0		$ 3,566

Gain (loss) on entity's disposition of equity in securities of subsidiaries. Reflects the difference in the parent company's carrying amount of the equity interest in the subsidiary immediately before and after all stock transactions.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Subparagraph g

-Article 9

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Data Type:	xbrli:monetaryItemType
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