Other non-current liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Other non-current liabilities
Operating lease liability	$ 115,130	$ 112,818
Tax payable	18,624	19,706
Finance lease liability	16,265	17,109
Other	6,617	3,367
Total other non-current liabilities	$ 156,636	$ 153,000