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Long-Term Debt, Schedule of Aggregate Payments Due on The Long-Term Debt (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Long-Term Debt [Abstract]      
2020 $ 150,016,000    
2021 0    
2022 0    
2023 381,250,000    
2024 343,750,000    
Thereafter 500,000,000    
Long-term Debt 1,375,016,000 $ 1,417,392,000  
Long-term Debt [Abstract]      
Payments on long-term debt 125,000,000 $ 0 $ 13,721,000
Revolving Credit Facility [Member]      
Long-term Debt [Abstract]      
Maximum borrowing capacity $ 850,000,000    
Credit facility, expiration date Mar. 27, 2024    
Commitment amount $ 25,000,000    
Credit facility, amount outstanding $ 0    
Revolving Credit Facility [Member] | LIBOR [Member]      
Long-term Debt [Abstract]      
Basis spread on variable rate 1.125%    
Revolving Credit Facility [Member] | Alternate Base Rate [Member]      
Long-term Debt [Abstract]      
Basis spread on variable rate 0.125%    
Letter of Credit [Member]      
Long-term Debt [Abstract]      
Credit facility, amount outstanding $ 5,258,000    
Term Loan [Member]      
Long-term Debt [Abstract]      
Maximum borrowing capacity $ 500,000,000    
Term of loan 5 years    
Debt instrument, frequency of periodic payment quarterly    
Percentage of unpaid balance payable on initial amount 65.00%    
Payments on long-term debt $ 125,000,000    
Credit facility, amount outstanding $ 375,000,000