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           Stockholders' Equity (Tables) 
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           Mar. 31, 2013 
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| Stockholders' Equity Note [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] | 
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| Schedule Of Share-based Compensation [Table Text Block] | 
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- Definition 
          Table of components of share-based compensation expense. No definition available. 
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- Definition 
          Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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