Other balance sheet items - Schedule of Other Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Pension obligation	$ 7,124		$ 7,124		$ 5,990
Operating lease liabilities	3,891		3,891		4,298
Unfavorable ground lease liability	1,912		1,912		1,967
Key money	15,877		15,877		16,731
Other	2,155		2,155		896
Total other liabilities	30,959		30,959		$ 29,882
Service cost component of net periodic pension cost	200	$ 200	400	$ 400
Non-service cost components of net periodic pension (benefit) cost	$ 100	$ 400	$ 500	$ 500