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Financial Instruments and Fair Value Measurement - Additional Information (Details) - USD ($)
3 Months Ended 12 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2020
Dec. 31, 2018
Derivative [Line Items]        
Fair value of long-term debt $ 3,054,000,000.0     $ 2,762,500,000
Carrying value of long-term debt 3,052,600,000     2,833,100,000
Anticipated reclassification of gains to earnings in the next twelve months 500,000      
Derivative Contracts Designated as Hedging Instruments | Instruments in a Cash Flow Hedging Relationship | Interest Rate Swap Agreements        
Derivative [Line Items]        
Interest risk derivatives, amount of ineffectiveness 0 $ 0    
Amounts excluded from the measure of effectiveness 0 0    
Derivative Contracts Designated as Hedging Instruments | Instruments in a Cash Flow Hedging Relationship | Commodity Contracts        
Derivative [Line Items]        
Amounts excluded from the measure of effectiveness $ 0 0    
Percentage of expected natural gas usage hedged, current year 50.00%      
Derivative Contracts Designated as Hedging Instruments | Instruments in a Cash Flow Hedging Relationship | Forward Exchange Contract        
Derivative [Line Items]        
Amounts excluded from the measure of effectiveness $ 0 0    
Notional amount of derivative 38,100,000     $ 51,600,000
Amounts forecasted and reclassified into earnings no longer probable 0 0    
Foreign currency risk derivatives, amount of ineffectiveness $ 0 $ 0    
Derivative Contracts Not Designated as Hedging Instruments | Maximum        
Derivative [Line Items]        
Foreign currency forward exchange contract term 18 months     18 months
Derivative Contracts Not Designated as Hedging Instruments | Forward Exchange Contract        
Derivative [Line Items]        
Notional amount of derivative $ 84,500,000     $ 62,200,000
Subsequent Event | Scenario, Forecast | Derivative Contracts Designated as Hedging Instruments | Instruments in a Cash Flow Hedging Relationship | Commodity Contracts        
Derivative [Line Items]        
Percentage of expected natural gas usage hedged, current year     20.00%