v2.4.0.8
Cash and Cash Equivalents, Short-term Investments and Fair Value of Financial Instruments (Details) avail for sasle securities levels 1-2-3 table (USD $)
9 Months Ended
Sep. 30, 2013
Dec. 31, 2012
Cash and Cash Equivalents [Line Items]    
Money Market Fund - daily traded value $ 1.00  
Cash, Cash Equivalents, and Short-term Investments 116,190,000 62,313,000
Fair Value, Measurements, Recurring [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash, Cash Equivalents, and Short-term Investments 64,775,000 38,891,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash, Cash Equivalents, and Short-term Investments 64,775,000 38,891,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash, Cash Equivalents, and Short-term Investments 0 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash, Cash Equivalents, and Short-term Investments 0 0
Money Market Funds [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure   38,891,000
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure 64,775,000 38,891,000
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure   38,891,000
Cash, Cash Equivalents, and Short-term Investments 64,775,000  
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure 0 0
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
   
Cash and Cash Equivalents [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure $ 0 $ 0