Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments - Narratives (Details)

v3.19.2
Financial Instruments - Narratives (Details)
€ in Thousands, $ in Thousands, MMBTU in Millions
1 Months Ended 6 Months Ended
Jul. 31, 2016
USD ($)
Jun. 30, 2019
USD ($)
MMBTU
Nov. 30, 2018
USD ($)
Feb. 28, 2018
EUR (€)
Natural gas swaps        
Derivative        
Derivative, notional quantity | MMBTU   3.9    
July 2016 interest rate cap        
Derivative        
Premium paid to acquire derivative instrument $ 1,551      
Derivative, cap interest rate   2.50%    
Derivative, notional amount $ 1,000,000      
July 2016 interest rate cap | Minimum        
Derivative        
Derivative, cap interest rate 1.50%      
July 2016 interest rate cap | Maximum        
Derivative        
Derivative, cap interest rate 3.00%      
November 2018 interest rate cap        
Derivative        
Derivative, cap interest rate     3.50%  
Derivative, notional amount     $ 500,000  
Currency swap        
Derivative        
Derivative, notional amount   $ 319,161   € 280,000
Cash flow hedging        
Derivative        
Amount of derivative loss expected to be transferred from OCI   $ 1,083