Revenue - Estimated future revenue (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)
Revenue
Total estimated future revenue	$ 995,502
Sales of fuel cell systems
Revenue
Total estimated future revenue	$ 34,553
Sale of hydrogen installations and other infrastructure
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Total estimated future revenue	$ 34,740
Sales of electrolyzers
Revenue
Total estimated future revenue	$ 269,371
Sales of engineered equipment
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Total estimated future revenue	$ 7,264
Services performed on fuel cell systems and related infrastructure
Revenue
Total estimated future revenue	131,112
Power purchase agreements
Revenue
Total estimated future revenue	375,119
Fuel delivered to customers and related equipment
Revenue
Total estimated future revenue	$ 82,733
Sales of cryogenic equipment and liquefiers
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Total estimated future revenue	$ 60,610
Maximum | Sales of fuel cell systems
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	2 years
Maximum | Sales of electrolyzers
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	2 years
Maximum | Services performed on fuel cell systems and related infrastructure
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	10 years
Maximum | Power purchase agreements
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	10 years
Maximum | Fuel delivered to customers and related equipment
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	10 years
Minimum | Sales of fuel cell systems
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Minimum | Sales of electrolyzers
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Minimum | Services performed on fuel cell systems and related infrastructure
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	5 years
Minimum | Power purchase agreements
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	5 years
Minimum | Fuel delivered to customers and related equipment
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	5 years