Debt - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	$ 35,261	$ 19,220	$ 100,840	$ 55,574
Derivatives in Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative	(3,789)		(3,789)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Expense)	(1,197)		(1,197)
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Fair value of derivative liability	5,100		5,100
Termination value in case of breach of provisions	5,100		5,100
Interest rate swaps | Derivatives in Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative	(3,789)		(3,789)
Interest rate swaps | Derivatives in Cash Flow Hedging | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Expense)	$ (1,197)		$ (1,197)