Revenue - Estimated future revenue (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($)
Revenue
Total estimated future revenue	$ 644,965
Sales of fuel cell systems
Revenue
Total estimated future revenue	14,758
Sale of hydrogen installations and other infrastructure
Revenue
Total estimated future revenue	17,781
Sale of electrolyzers
Revenue
Total estimated future revenue	77,061
Sales of engineered equipment
Revenue
Total estimated future revenue	48,607
Services performed on fuel cell systems and related infrastructure
Revenue
Total estimated future revenue	93,371
Power purchase agreements
Revenue
Total estimated future revenue	252,003
Fuel delivered to customers and related equipment
Revenue
Total estimated future revenue	81,785
Sale of cryogenic equipment
Revenue
Total estimated future revenue	$ 59,599
Maximum | Sales of fuel cell systems
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Maximum | Sale of hydrogen installations and other infrastructure
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	1 year
Maximum | Services performed on fuel cell systems and related infrastructure
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	7 years
Maximum | Power purchase agreements
Revenue
Duration of estimated revenue expected to be recognized in future (in years)	7 years
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