|**Share-Based Payments (Tables)**                                                      | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                     
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|**Disclosure of Compensation Related Costs, Share-based Payments [Abstract]**          |                                                                                                                                                                                                                                                                                                                                                                                                                                     
|Schedule of Weighted-Average Assumptions Used to Determine Fair Value of Stock Options | The fair values of the options granted during the years endedDecember 31, 2013,2012, and2011have been estimated at the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:For the Year Ended December 31,201320122011Expected volatility41.8%42.8%41.5%Risk-free interest rate1.4%1.4%2.8%Expected life (years)7.27.06.7Dividend yield0.0%0.0%0.0%                             
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|                                                                                       | For the Year Ended December 31,                                                                                                                                                                                                                                                                                                                                                                                                     
|                                                                                       | 2013                                                                                                                                                                                                                                                                                                                                                                                                                                
|Expected volatility                                                                    | 41.8                                                                                                                                                                                                                                                                                                                                                                                                                                
|Risk-free interest rate                                                                | 1.4                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Expected life (years)                                                                  | 7.2                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Dividend yield                                                                         | 0.0                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Schedule of Stock Option Activity                                                      | A summary of our stock option activity and related information is as follows:Shares(In Thousands)Weighted- Average Exercise Price per ShareWeighted- Average Remaining Life (Years)Aggregate Intrinsic Value(In Millions)Outstanding, December 31, 20122,575$21.12Granted14124.17Exercised(338)24.39Forfeitures——Expirations(17)24.47Outstanding, December 31, 20132,36120.824.5$29.5Exercisable, December 31, 20131,99120.453.825.6
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|                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                     
|                                                                                       | Shares(In Thousands)                                                                                                                                                                                                                                                                                                                                                                                                                
|Outstanding, December 31, 2012                                                         | 2,575                                                                                                                                                                                                                                                                                                                                                                                                                               
|Granted                                                                                | 141                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Exercised                                                                              | (338                                                                                                                                                                                                                                                                                                                                                                                                                                
|Forfeitures                                                                            | —                                                                                                                                                                                                                                                                                                                                                                                                                                   
|Expirations                                                                            | (17                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Outstanding, December 31, 2013                                                         | 2,361                                                                                                                                                                                                                                                                                                                                                                                                                               
|Exercisable, December 31, 2013                                                         | 1,991                                                                                                                                                                                                                                                                                                                                                                                                                               
|Schedule of Restricted Stock Activity                                                  | A summary of our issued restricted stock awards is as follows (share information in thousands):SharesWeighted-Average Grant Date Fair ValueNonvested shares at December 31, 20121,048$19.28Granted84723.55Vested(690)18.25Forfeited(43)22.67Nonvested shares at December 31, 20131,16222.89                                                                                                                                         
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|                                                                                       | Shares                                                                                                                                                                                                                                                                                                                                                                                                                              
|Nonvested shares at December 31, 2012                                                  | 1,048                                                                                                                                                                                                                                                                                                                                                                                                                               
|Granted                                                                                | 847                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Vested                                                                                 | (690                                                                                                                                                                                                                                                                                                                                                                                                                                
|Forfeited                                                                              | (43                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Nonvested shares at December 31, 2013                                                  | 1,162                                                                                                                                                                                                                                                                                                                                                                                                                               

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