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           Deferred Income (Tables) 
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           Jun. 30, 2012 
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| Deferred Income (Tables) [Abstract] | |||||||||||||||||||||||||||||||||||||||||||
| Deferred Income By Arrangement Disclosure [Table Text Block] | 
 Deferred income at the end of each period was as follows: 
 
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- Definition 
          Deferred Income By Arrangement Disclosure [Table Text Block] No definition available. 
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- Details 
          
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