| 
           Subsequent Events (Details) (Senior Secured Notes Due 2021 [Member], Issuance of Debt [Member], USD $) 
        In Millions, unless otherwise specified  | 
        
           Feb. 28, 2013 
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|---|---|
| 
           Senior Secured Notes Due 2021 [Member] | Issuance of Debt [Member] 
         | 
        |
| Subsequent Event [Line Items] | |
| Debt instrument principal amount | $ 1,500.0 | 
| Debt instrument stated interest rate | 5.625% | 
| X | ||||||||||
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- Definition 
          The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
        
| X | ||||||||||
| 
             
- Definition 
          Interest rate stated in the contractual debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
        
| X | ||||||||||
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- Details 
          
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