Annual report pursuant to Section 13 and 15(d)

Financial Instruments - Narratives (Details)

v3.10.0.1
Financial Instruments - Narratives (Details)
€ in Thousands, MMBTU in Millions
1 Months Ended 12 Months Ended
Jul. 31, 2016
USD ($)
Dec. 31, 2018
USD ($)
MMBTU
Dec. 31, 2018
EUR (€)
Nov. 13, 2018
USD ($)
Derivative [Line Items]        
Derivative, notional quantity (in MMBTU) | MMBTU   3.9    
Amount of derivative loss expected to be transfered from OCI   $ 640,000    
Cross currency swap        
Derivative [Line Items]        
Derivative, notional amount   $ 320,404,000 € 280,000  
Interest rate caps        
Derivative [Line Items]        
Premium paid to acquire derivative instrument $ 1,551,000      
Derivative, cap interest rate   2.50% 2.50%  
Derivative, notional amount $ 1,000,000,000      
Interest rate caps | Minimum        
Derivative [Line Items]        
Derivative, cap interest rate 1.50%      
Interest rate caps | Maximum        
Derivative [Line Items]        
Derivative, cap interest rate 3.00%      
Interest rate cap II        
Derivative [Line Items]        
Derivative, cap interest rate       3.50%
Derivative, notional amount       $ 500,000