Employee Benefit Plans - Change in benefit obligation (Details) - Foreign Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Change in benefit obligations
Benefit obligations, beginning balance	$ 24,855	$ 27,431
Gross service cost	1,107	1,587	$ 1,549
Interest cost	138	53	106
Employee contributions	437	499
Actuarial (gains)/losses	(4,676)	(2,185)
Benefits (paid), net of transfers	(2,361)	(432)
Curtailments & settlements	(799)	(492)
Foreign exchange adjustment	(986)	(1,606)
Benefit obligations, ending balance	$ 17,715	$ 24,855	$ 27,431