XML 69 R58.htm IDEA: XBRL DOCUMENT v3.8.0.1
Long-term Debt (Details) - USD ($)
9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Jun. 30, 2017
Feb. 21, 2017
Feb. 20, 2017
Dec. 31, 2016
Borrowings            
Unamortized discount, debt issuance costs, and other $ (3,100,000)         $ (3,600,000)
Total long term-debt 781,900,000         $ 596,400,000
Borrowings under the facility $ 491,000,000.0 $ 0        
3.75% senior notes due 2022            
Borrowings            
Interest rate (as a percent) 3.75%         3.75%
Long-term debt, carrying amount $ 350,000,000.0         $ 350,000,000.0
3.75% senior notes due 2022 | Significant Observable Inputs (Level 2)            
Borrowings            
Fair value of notes $ 359,100,000         $ 347,200,000
5.125% senior notes due 2020            
Borrowings            
Interest rate (as a percent) 5.125%         5.125%
Long-term debt, carrying amount $ 250,000,000.0         $ 250,000,000.0
5.125% senior notes due 2020 | Significant Observable Inputs (Level 2)            
Borrowings            
Fair value of notes 267,600,000         263,100,000
Revolving credit facility | Credit Agreement            
Borrowings            
Revolving credit facility 185,000,000.0         0
Maximum borrowing capacity       $ 1,000,000,000.0 $ 600,000,000.0  
Debt issuance costs     $ 1,400,000      
Additional borrowing capacity         500,000,000.0  
Borrowings under the facility $ 491,000,000.0          
Debt instrument, interest rate during period 2.65%          
Effective interest rate (percent) 2.33%          
Availability under revolving line of credit $ 815,000,000.0          
Revolving credit facility | Credit Agreement | Significant Observable Inputs (Level 2)            
Borrowings            
Fair value of revolving credit facility $ 185,000,000.0         $ 0
Letter of Credit | Credit Agreement            
Borrowings            
Maximum borrowing capacity         $ 50,000,000.0