Other Non-current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Other Non-current Liabilities [Abstract]
Operating lease liability	$ 109,014
Tax payable	20,464	$ 22,583
Finance lease obligation	14,710	10,146
Other	3,266	9,251
Other non-current liabilities, Total	$ 147,454	$ 41,980