Revenue from contracts with customers - Contract balances (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Contract assets	$ 163,466	$ 158,861
Change in contract assets	4,605
Contract liabilities - current	(193,299)	(202,144)
Change in contract liabilities - current	8,845
Contract liabilities - noncurrent	(2,130)	(291)
Change in contract liabilities - noncurrent	(1,839)
Net contract liabilities	(31,963)	$ (43,574)
Change in net contract assets (liabilities)	$ 11,611