Other non-current liabilities (Details) - USD ($)	Mar. 31, 2022	Mar. 17, 2022	Dec. 31, 2021
Other non-current liabilities
Operating lease liability	$ 112,892,000	$ 4,477,000	$ 109,882,000
Tax payable	19,209,000		18,859,000
Finance lease liability	13,747,000		13,983,000
Other	4,257,000		4,536,000
Total other non-current liabilities	$ 150,105,000		$ 147,260,000