| 
           CUSTOMER CONTRACTS AND OTHER INTANGIBLE ASSETS (Details 2) (USD $) 
        In Thousands, unless otherwise specified  | 
        12 Months Ended | 
|---|---|
| 
           Dec. 31, 2011 
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      |
| Estimated amortization expense for the existing carrying amount of customer contracts and other intangible assets | |
| 2012 | $ 21,675 | 
| 2013 | 20,780 | 
| 2014 | 17,771 | 
| 2015 | 15,113 | 
| 2016 | $ 12,342 | 
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- Details 
          
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- Definition 
          The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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