For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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-Section 50

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 275

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Name:	us-gaap_ConcentrationRiskPercentage
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Data Type:	num:percentItemType
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Summary of Significant Accounting Policies (Details 6)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net revenues \| International
Certain risks and concentrations
Percentage of concentration	18.00%	15.00%	14.00%
Net revenues \| Single customer \| Maximum
Certain risks and concentrations
Percentage of concentration	10.00%	10.00%	10.00%
Accounts receivable \| Single customer \| Maximum
Certain risks and concentrations
Percentage of concentration	10.00%	10.00%