Financing Agreements - Additional Information (Details) - USD ($)
 3 Months Ended
Mar. 31, 2018
Sep. 18, 2017
Sep. 14, 2017
Aug. 17, 2017
Apr. 04, 2017
Mar. 31, 2018
Dec. 31, 2017
 [1]
Debt Instrument [Line Items]              
Loss on extinguishment of debt         $ 6,000,000    
Line of Credit [Member]              
Debt Instrument [Line Items]              
Current aggregate facility $ 275,000,000         $ 275,000,000  
Revolving Facility [Member]              
Debt Instrument [Line Items]              
Current aggregate facility 600,000,000         $ 600,000,000  
Deferred financing payments       $ 2,000,000      
Fronting fee rate           0.125%  
Amount outstanding 0         $ 0  
Utilized for letters of credit 22,000,000         22,000,000  
Available borrowing capacity 578,000,000         578,000,000  
Revolving Facility [Member] | Maximum [Member]              
Debt Instrument [Line Items]              
Amount that may be applied to letters of credit $ 275,000,000         $ 275,000,000  
Senior Notes Due September 2021 [Member]              
Debt Instrument [Line Items]              
Senior notes redeemed   $ 350,000,000     $ 100,000,000    
Debt redemption price   102.688%     104.031%    
Loss on extinguishment of debt   $ 13,000,000          
Redemption premium   10,000,000     $ 4,000,000    
Write-off of deferred financing costs   $ 3,000,000     1,000,000    
Senior Notes Due April 2025 [Member]              
Debt Instrument [Line Items]              
Senior notes issued         $ 400,000,000    
Interest rate 5.75% [1]       5.75% 5.75% [1] 5.75%
Net proceeds         $ 394,000,000    
Financing costs         6,000,000    
Senior Notes Due April 2025 [Member] | Cash Flow Hedging [Member]              
Debt Instrument [Line Items]              
Interest rate 5.75%         5.75%  
Derivative, fixed interest rate 3.85%         3.85%  
Senior Notes Due April 2025 [Member] | Currency Swap [Member] | Cash Flow Hedging [Member]              
Debt Instrument [Line Items]              
Derivative, fixed interest rate 3.85%         3.85%  
Other indebtedness [Member]              
Debt Instrument [Line Items]              
Redemption premium         $ 1,000,000    
Term Facility [Member]              
Debt Instrument [Line Items]              
Net proceeds     $ 274,000,000        
Financing costs     $ 1,000,000        
Periodic payments as a percentage of the initial principal amount 1.5625%            
Interest rate at period end 4.052%         4.052%  
[1] In conjunction with the issuance of the April 2025 Notes we entered into 8-year fixed-to-fixed cross-currency swaps which have the effect of economically converting the April 2025 Notes to euro-denominated debt at a fixed rate of 3.850%. In conjunction with the issuance of the June 2026 Notes we entered into 10-year fixed-to-fixed cross-currency swaps which have the effect of economically converting the June 2026 Notes to euro-denominated debt at a fixed rate of 5.140%. See Note 14 for additional information.