Other Non-current Assets (Schedule of Other Non-current Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other Non-current Assets [Abstract]
Tax receivable (note 8)	$ 12,851	$ 10,035
Deferred debt issue costs (note 25)	3,768	6,182
Other non-current assets	7,527	4,027
Other Non-current Assets, Total	$ 24,146	$ 20,244