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Summary of Significant Accounting Policies (Details) (USD $)
3 Months Ended
Mar. 31, 2013
Cash Equivalents and Concentrations of Credit Risk [Abstract]  
Maximum number of months of investments with original maturities from date of acquisition to be cash equivalents 3 months
Accounts Receivable [Abstract]  
Uncollectable, accounts receivable $ 0
Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Estimated useful lives 3 years
Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Estimated useful lives 7 years