Revenue - Changes in contract assets and contract liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Contract assets
Contract asset impairment charge	$ 2,400	$ 0
Net change in contract assets	(40,258)	(39,515)	$ (10,608)
Contract liabilities
Increases due to cash received, net of amounts recognized as revenue during the period	151,965	200,347
Change in contract liabilities related to warrants	440
Contract liabilities assumed as part of acquisitions		10,011
Revenue recognized that was included in the contract liability balance as of the beginning of the period	(94,001)	(163,550)
Net change in deferred revenue and contract liabilities	58,404	46,808
Sales of fuel cell systems
Contract assets
Transferred to receivables from contract assets recognized at the beginning of the period	(94,860)	(33,394)
Change in contract assets related to warrants	14,260	26,455
Contract asset impairment charge	(2,375)
Revenue recognized and not billed as of the end of the period	134,677	72,469
Net change in contract assets	$ 51,702	$ 65,530