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Debt - Additional Information (Detail)
3 Months Ended
Mar. 31, 2018
USD ($)
extension
Dec. 31, 2017
USD ($)
Debt Instrument [Line Items]    
Line of Credit Facility, Remaining Borrowing Capacity $ 488,900,000  
Long-term debt, maturities, repayments of principal, remainder of 2018 12,500,000  
Long-term debt, maturities, repayments of principal in 2019 12,500,000  
Long-term debt, maturities, repayments of principal in 2020 14,100,000  
Long-term debt, maturities, repayments of principal in 2021 295,300,000  
Long-term debt, maturities, repayments of principal in 2022 291,800,000  
Long-term debt, maturities, repayments of principal in the years thereafter $ 275,000,000  
Senior Notes    
Debt Instrument [Line Items]    
Rate of interest discounted 0.30%  
Revolving Credit Facility    
Debt Instrument [Line Items]    
Maximum borrowing capacity $ 600,000,000  
Number of extensions | extension 2  
Term of each extension (in years) 1 year  
Revolving Credit Facility | Minimum    
Debt Instrument [Line Items]    
Commitment fee charged on unused portion of facility 0.125%  
Revolving Credit Facility | Maximum    
Debt Instrument [Line Items]    
Commitment fee charged on unused portion of facility 0.25%  
Term Loan    
Debt Instrument [Line Items]    
Long-term debt, gross $ 250,000,000  
Revolving Credit Facility, Additional Borrowing Capacity    
Debt Instrument [Line Items]    
Maximum borrowing capacity 200,000,000  
2021 Notes | Senior Notes    
Debt Instrument [Line Items]    
Senior notes, par value $ 275,000,000  
Interest rate of debt 3.875%  
Debt issued, percent of par 99.50%  
Effective yield, percentage 3.951%  
Long-term Debt, Fair Value $ 272,700,000 $ 278,100,000
2024 Notes | Senior Notes    
Debt Instrument [Line Items]    
Senior notes, par value $ 275,000,000  
Interest rate of debt 4.375%  
Debt issued, percent of par 99.60%  
Effective yield, percentage 4.422%  
Long-term Debt, Fair Value $ 271,200,000 $ 277,900,000
2021 and 2024 Notes | Senior Notes    
Debt Instrument [Line Items]    
Senior notes redemption price, percentage 100.00%  
Letter of Credit    
Debt Instrument [Line Items]    
Long-term Line of Credit $ 104,300,000  
Letters of Credit Outstanding, Amount 6,800,000  
European Lease Agreement | Replaced Line Of Credit    
Debt Instrument [Line Items]    
Letters of Credit Outstanding, Amount $ 1,300,000  
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility    
Debt Instrument [Line Items]    
Best instrument, basis spread on variable rate 1.50%