Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Fair Value Of Assets And Liabilities) (Details)

v3.3.1.900
Fair Value Measurements (Fair Value Of Assets And Liabilities) (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Jan. 27, 2015
Dec. 31, 2014
Apr. 24, 2012
Credit Agreement Terminated January 27, 2015 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt       $ 600,000
Credit Agreement Terminated January 27, 2015 [Member] | Long-term Debt [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt $ 0 $ 228,126 $ 228,126 $ 250,000
Secured debt, fair value     228,126  
Credit Agreement Terminated January 27, 2015 [Member] | Long-term Debt [Member] | Level 1 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value     0  
Credit Agreement Terminated January 27, 2015 [Member] | Long-term Debt [Member] | Level 2 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value     228,126  
Credit Agreement Terminated January 27, 2015 [Member] | Long-term Debt [Member] | Level 3 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value     0  
Credit Agreement Terminated January 27, 2015 [Member] | Revolving Credit Facility [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt 0   0  
Credit Agreement 1.25B [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt   1,250,000    
Credit Agreement 1.25B [Member] | Long-term Debt [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt 500,000 $ 500,000 0  
Secured debt, fair value 500,000      
Credit Agreement 1.25B [Member] | Long-term Debt [Member] | Level 1 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value 0      
Credit Agreement 1.25B [Member] | Long-term Debt [Member] | Level 2 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value 500,000      
Credit Agreement 1.25B [Member] | Long-term Debt [Member] | Level 3 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value 0      
Credit Agreement 1.25B [Member] | Revolving Credit Facility [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt 140,000   $ 0  
Secured debt, fair value 140,000      
Credit Agreement 1.25B [Member] | Revolving Credit Facility [Member] | Level 1 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value 0      
Credit Agreement 1.25B [Member] | Revolving Credit Facility [Member] | Level 2 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value 140,000      
Credit Agreement 1.25B [Member] | Revolving Credit Facility [Member] | Level 3 [Member]        
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]        
Secured debt, fair value $ 0