v3.19.3
Derivative financial instruments (Details) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Dec. 31, 2018
Breakdown of fair value amount of derivative financial instruments [Abstract]      
Loss on cash flow hedges $ 41,062 $ 51,049  
Cash Flow Hedge [Member]      
Breakdown of fair value amount of derivative financial instruments [Abstract]      
Assets 5,994   $ 13,153
Liabilities $ 341,590   279,152
Interest Rate Derivatives [Member] | Euros [Member]      
Breakdown of fair value amount of derivative financial instruments [Abstract]      
Percent of notional amount of debt hedged in next 12 months 100.00%    
Percentage of notional amount of debt hedged in year two 75.00%    
Interest Rate Derivatives [Member] | Cash Flow Hedge [Member]      
Breakdown of fair value amount of derivative financial instruments [Abstract]      
Assets $ 1,143   9,923
Liabilities 341,590   279,152
Loss on cash flow hedges (41,100) $ (51,000)  
After-tax result accumulated in equity 35,800   95,000
Foreign Exchange Derivative Instruments [Member] | Cash Flow Hedge [Member]      
Breakdown of fair value amount of derivative financial instruments [Abstract]      
Assets 4,850   3,230
Liabilities $ 0   $ 0