| 
           Fair Value Measurements (Details 2) (KEYW Holding Corporation, USD $) 
        In Millions, except Share data, unless otherwise specified  | 
        3 Months Ended | |
|---|---|---|
| 
           Mar. 31, 2012 
         | 
        
           Dec. 31, 2011 
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      |
| 
           KEYW Holding Corporation 
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        ||
| Schedule of Trading Security [Line Items] | ||
| Number of shares owned in investee (in shares) | 1,900,000 | |
| Percentage of common stock owned | 7.00% | |
| Amount of sale of owned shares | $ 14.0 | |
| Warrants | ||
| Number of warrants owned (in shares) | 50,000 | 50,000 | 
| Exercise price of warrants (in dollars per share) | $ 9.25 | $ 9.25 | 
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- Details 
          
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- Definition 
          Represents the amount of shares of common stock owned in the investee accounted for as a trading security that were sold. No definition available. 
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- Definition 
          The percentage of ownership of common stock or equity participation in the investee accounted for as a trading security No definition available. 
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- Definition 
          The exercise price of each class of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The specified number of securities that each class of warrants or rights outstanding give the holder the right but not the obligation to purchase from the issuer at a specific price, on or before a certain date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Balance held at close of period in number of shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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